In the previous post here we saw how to read external files in Cypress using cy.readFile. Cypress also provides another way to read files. In this post, I will show how to Fixtures to do data driven testing in Cypress.

Syntax

According to documentation, syntax is as below.

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cy.fixture(filePath)
cy.fixture(filePath, encoding)
cy.fixture(filePath, options)
cy.fixture(filePath, encoding, options)

Comparison with cy.readFile

Main difference between cy.readFile and cy.Fixture is that former one starts looking for the files from project root folder and later looks for files under Fixture folder. cy.Fixture supports a wide range of file types/extensions like json, txt, html,jpeg,gif,png etc. If file name is not specified it looks for all supported filetypes in specific order starting with JSON. We can even assign alias to this , which will help to reuse this later on.

Example

To demonstrate this, let’s revisit old example of logging into SauceDemo website. This time, instead of using hardcoded values in feature file, I will move credentials into a separate JSON file and keep it inside Fixtures\TestDataFiles folder . File should look like below. This has two set of login credentials.

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[

    {
        "UserType" :"LockedOutUser",
        "UserName" : "locked_out_user",
        "Password" : "secret_sauce"
    },
    {
        "UserType" :"StandardUser",
        "UserName" : "standard_user",
        "Password" : "secret_sauce"
    }
]

Feature File

Create a new scenario to login to ECommerce site by using Fixtures. In below scenario we just specify type of User which we need to use for this scenario. I am specifying a user type here since there are different types of users and we can have different scenarios for them.

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@focus
  Scenario: Logging into ECommerce Site as Standard User
    Given I Login to Demo shopping page as 'StandardUser'
    Then I should see products listed
    

Step Definition

Step definition file for this will look like below. In Step definition files, below steps are performed.

  • Reading test data file by using cy.fixture() by passing relative path from Fixture folder and then alias it into a variable loginCredentials. The hierarchy is separated by forward slashes.
  • Get the JSON object ( which is an array of objects) from above step and identify the specific object which we need to use for this step based on the UserType specified in feature file. This is achieved by using filter method. This is mostly like LINQ in C# . More details can be found here . This filter will return an array of object which satisfy filter criteria specified. In this case, there will be only one object in array.
  • Login to the demo website by using first user in the above array.
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//Navigate to URl and login using credentials from Fixture
const url = 'https://www.saucedemo.com/index.html'
Given('I Login to Demo shopping page as {string}', (UserTypeValue) => {
  cy.visit(url);

  //Reading Json file and then alias it
  cy.fixture('TestDataFiles/LoginCredentials.json').as('loginCredentials');
  cy.log('Value passed in' +UserTypeValue);

  //Use alias and identify the object which matched to the information passed from feature file
  cy.get('@loginCredentials').then((user) => {

     // Find the object corresponding to UserType passed in
      var data = user.filter(item => (item.UserType == UserTypeValue));


      //printout details
      var propValue;
      cy.log('filtered data :'+data[0]);
      for(var propName in data[0]) {
        propValue = data[0][propName]

        cy.log(propName,propValue);
        }

       //Login
      cy.get('#user-name').type(data[0].UserName);
      cy.get('#password').type(data[0].Password,{log:false});
  });

    cy.get('#login-button').click();
});

Test Output

Now it is time to run above scenario. Open Cypress by running command npx cypress open

Run the scenario on cypress UI and result will look like below. We can clearly see that assertions are passed.

Fixture-ResultImage

In the previous post here and here, we saw how to write BDD test cases using cucumber along with Cypress and to use datatables. As we saw in those examples, we are hard coding few data in feature files. This is not a best practise since we need to modify the feature file for every new set of data. Assuming we need to have different data in different environments, this will make it hard to run the tests across various test environment. Let us look at how we can make read these data from a file outside of feature file.

Cypress provides two options to read external files. They are readFile and Fixtures. In this blog post, let us look into readFile method and how to use it.

readFile

According to documentation, the command syntax is as below

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cy.readFile(filePath)
cy.readFile(filePath, encoding)
cy.readFile(filePath, options)
cy.readFile(filePath, encoding, options)

cy.readFile() command look for the file to be present in default project root folder .Hence filepath should be specified relative to the root folder . For any files other than JSON format, this command yields the content of the file. For JSON files, the content is parsed into Javascript and returned.

FeatureFile

Let us write a new scenario to read both text file and json file. We then assert the content of the files.

ReadFile-FeatureFileImage

Step Definition

Corresponding Step definition will look like below. Here we get information from datatable and assert the text file content as is. For JSON files, cypress yields a JSON object . Hence we convert the expected text to json object and assert on its properties.

ReadFile-StepDefinitionImage

Test Output

Now it is time to run above scenario. Open Cypress by running command npx cypress open

Run the scenario on cypress UI and result will look like below. We can clearly see that assertions are passed.

ReadFile-ResultImage

Normally every project will have some values to be read from config files like user name, connection strings, environment specific details etc.

Dotnet Framework

In dotnet framework projects, this can be easily done by using Configuration Manager. This is available when we add System.Configuration assembly reference.

Let us look at an example of a app config file like below

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<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
  </startup>
  <appSettings>
    <add key="Url" value="https://www.saucedemo.com/"/>
    <add key="UserName" value="standard_user"/>
    <add key="Password" value="secret_sauce"/>
  </appSettings>
</configuration>

Storing user name and password in app config is not a best practise. For sake of simplicity , let us keep it here. In dotnet framework , we can read above config values with below

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var Url = ConfigurationManager.AppSettings["Url"];
var UserName = ConfigurationManager.AppSettings["UserName"];
var Password = ConfigurationManager.AppSettings["Password"];

Dotnet Core

Now let us look how to read above config values in a dotnet core project .

Let us look at a appsettings.json file

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{
  "SauceDemoDetails": {
    "Url": "https://www.saucedemo.com/",
    "UserName": "standard_user",
    "Password": "secret_sauce"
  },
  "MyKey":  "My appsettings.json Value",
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft": "Warning",
      "Microsoft.Hosting.Lifetime": "Information"
    }
  },
  "AllowedHosts": "*"
}

There are different approaches to read the config file. Let us look at couple of them.

IConfiguration

One of the approach to consume this is using IConfiguration Interface. We can inject this to the class constructor where we need to consume these config values.

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//This is not entire class file. It just show the main areas where we need to make changes.

//Using statement
using Microsoft.Extensions.Configuration;

// Make sure to create a private variable and inject IConfiguration to constructor

IConfiguration _configuration;
public demo(IConfiguration configuration)
{
    _configuration = configuration;
}


//Usage is as below. Use GetValue method and specify the type. 
//Also we need to give entire hierarchy staring with section value to the keyname separated by :

var Url = _configuration.GetValue<string>("SauceDemoDetails:Url");
var UserName = _configuration.GetValue<string>("SauceDemoDetails:UserName");
var Password = _configuration.GetValue<string>("SauceDemoDetails:Password");

However injecting IConfiguration is not a good practise since we are not sure what configuration is this class now depend on. Also class should know the entire hierarchy of configuration making it tightly coupled.

IOptions

Another way to access these config values is by using Options Pattern . Documentation of that can be found here. The options pattern uses classes to provide strongly typed access to groups of related settings. It also provides way to validate details.

In this pattern, we need to create an options class corresponding to the config value

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public class SauceDemoDetailsOptions
{
    public const string SauceDemoDetails = "SauceDemoDetails";

    public string Url { get; set; }
    public string UserName { get; set; }
    public string Password { get; set; }
}

According to documentation, options class should be non abstract class with public parameterless constructor. All public get - set properties of the type are bound and fields are not bound. Hence in above class, Url, UserName, Password are bound to config values and SauceDemoDetails are not bound.

Let us see how we can bind the configuration file to above created class. In startup.cs file, do below

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// Use configuration builder to load the appsettings.json file

public Startup(IHostingEnvironment env)
{
    var builder = new ConfigurationBuilder()
        .SetBasePath(env.ContentRootPath)
        .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
        .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true);

    if (env.IsDevelopment())
    {
        builder.AddUserSecrets();
    }

    builder.AddEnvironmentVariables();
    Configuration = builder.Build();
}

// Configure Services to bind
//Need to give entire hierarchy separated by : . In below example, I use the constant string from the class to specify so that it doesn't need to be hard coded here.
public void ConfigureServices(IServiceCollection services)
{
    services.Configure<SauceDemoDetailsOptions>(Configuration.GetSection(SauceDemoDetailsOptions. SauceDemoDetails));
}

Inorder to use this, we need to inject IOptions to the consuming class.

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//This is not entire class file. It just show the main areas where we need to make changes.

//Using statement
using Microsoft.Extensions.Options;

// Make sure to create a private variable and inject IOptions to constructor. IOptions expose Value property which contains the details of object.

private SauceDemoDetailsOptions _ sauceDemoDetailsOptions;
public demo(IOptions<SauceDemoDetailsOptions> sauceDemoDetailsOptions)
{
    _sauceDemoDetailsOptions = sauceDemoDetailsOptions.Value;
}

//Usage is as below.  :

var Url = _sauceDemoDetailsOptions.Url;
var UserName = _sauceDemoDetailsOptions.UserName;
var Password = _sauceDemoDetailsOptions.Password;

One important point to remember is Ioptions interface doesn’t support reading configuration data after app has started. Hence any changes to appsettings.json after the app has started will not be effective till next restart. If we need to recompute the values every-time, then we should use IOptionsSnapshot interface. This is a scoped interface which cannot be injected to Singleton service. The usage of this is same as IOptions interface. We also need to make sure that configuration source also supports reload on change.

Validations

Let us look into how to implement validations into this. In above examples, if there are any mistakes like typo ,missing fields etc, then those fields will not be bound. However it will not error out there and will continue execution , till it throws an exception where it require these missing fields. We can add validations from DataAnnotations library to identify these earlier.

DataAnnotations provide various validator attributes like Required, Range, RegularExpression, String Length etc.

Let us add [Required] to all properties as below.

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using System.ComponentModel.DataAnnotations;
public class SauceDemoDetailsOptions
{
    public const string SauceDemoDetails = "SauceDemoDetails";
 [Required]
    public string Url { get; set; }
    [Required]
    public string UserName { get; set; }
    [Required]
    public string Password { get; set; }
}

We will also have to change the startup class to do validations after we bind.

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public void ConfigureServices(IServiceCollection services)
{

services.AddOptions<SauceDemoDetailsOptions>()
        .Bind(Configuration.GetSection(SauceDemoDetailsOptions. SauceDemoDetails)
        .ValidateDataAnnotations();
      

}

In the previous post here, we saw how to use cucumber along with Cypress. The demo scenario we saw was a basic example. Now let us look into how we can use datartable in cypress cucumber.

Feature File

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Feature: Demo for BDD in Cypress

  I want to demo using BDD in Cypress
  
  @focus
  Scenario: Logging into ECommerce Site
    Given I open Demo shopping page
    When I login as 'standard_user' user
    Then I should see products listed
    Given I add below products to cart
    |ProductName                |Qty|
    |Sauce Labs Backpack        |1  |
    |Sauce Labs Fleece Jacket   |1  |
    |Sauce Labs Onesie          |1  |
    

The step definition file will be as below

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// Import Given , When, then from cypress-cucumber-preprocessort steps
import { Given, When, Then } from "cypress-cucumber-preprocessor/steps";

//Navigate to URl
const url = 'https://www.saucedemo.com/index.html'
Given('I open Demo shopping page', () => {
  cy.visit(url)
});

//Type in user name and password. Username is passed from feature file. For demo purpose password is hard coded
// We specify what is the type of variable in step ..See {string}
//Password is not logged by providing the option
When("I login as {string} user", (username) => {
    cy.get('#user-name').type(username);
    cy.get('#password').type('secret_sauce',{log:false});
    cy.get('#login-button').click();
  });


//Get list of children and assert its length
Then('I should see products listed', () => {
  cy.get('div.inventory_list').children().should('have.length', 6);
  });

//Use datatable to click on each element
//Identify the elements based on the product name and click corresponding add to cart button

  Given('I add below products to cart', (dataTable) => {

    cy.log('raw : ' + dataTable.raw());
    cy.log('rows : ' + dataTable.rows());
    cy.log('HASHES : ' );
    var propValue;
    dataTable.hashes().forEach(elem =>{
      for(var propName in elem) {
        propValue = elem[propName]

        cy.log(propName,propValue);
    }
    });

    dataTable.hashes().forEach(elem => {
      cy.log("Adding "+elem.ProductName);
      cy.get('.inventory_item_name').contains(elem.ProductName).parent().parent().next().find('.btn_primary').click();
      });


  });


datatable can be used in few different ways . Documentation of cucumberjs is here. I have used datatable.Hashes which return an array of hashes where column name is the key. Apart from datatable.Hashes, there are other methods like row( return a 2D array without first row) , raw( return table as 2D array) , rowsHash(where first column is key and second column is value) etc.

Running this in Cypress will result in below. we can see the values logged by cy.log

Result Result

As discussed in previous posts here and here, we use Cypress for writing tests to validate GUI and API tests. In many companies we use behaviour driven development practises where the requirements or acceptance criteria are specified in Gherkin format. As a results, test automation scenarios are also written in Gherkin format. Cucumber , Specflow etc are some of such framework used extensively . In this post, let us examine how we can write BDD test cases in Cypress.

First step is to identify , how we can run Gherkin sytanxed specs with Cypress. This is done with help of cypress-cucumber-preprocessor.

Installation

Installation of this package is straight forward

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npm install --save-dev cypress-cucumber-preprocessor

Configure

Once NPM package is installed, then next step is to configure Cypress to use it. It consist of 3 main steps.

  • Add below code to cypress/package/index.js file.
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const cucumber = require('cypress-cucumber-preprocessor').default

module.exports = (on, config) => {
  on('file:preprocessor', cucumber())
}
  • Modify package.json to add below line
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"cypress-cucumber-preprocessor": {
  "nonGlobalStepDefinitions": true
}

nonGlobalStepDefinitions is set as true, which means Cypress Cucumber Preprocessor Style pattern will be used for Step definitions. Default value is false which means old cucumber format of everything global will be used.

There are some other configuration values which we can specify . Details are available in above project documentation link.

  • Add support for feature files in cypress.json.
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{
  "testFiles": "**/*.{feature,features}"
}

Normally browser is relaunched for each feature files which will result in extended test execution time. cypress-cucumber-preprocessor provides a way to combine all files into a single features file. Above snippet shows that we can expected files named as .feature and .features.

Feature Files

Now it is time to add a feature file. Add a demo.feature file inside Integration/Feature folder. Add below Gherkin into that file

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Feature: Demo for BDD in Cypress

  I want to demo using BDD in Cypress
  
  @focus
  Scenario: Logging into ECommerce Site
    Given I open Demo shopping page
    When I login as "standard_user" user
    Then I should see products listed
    

Step Definitions

Recommended way is to create Step definiton files in a folder named as Feature and keep it inside where we have feature files. Let us create a demosteps.js file.

Location of feature file : Integration/Feature/demo.feature.

Location of StepDefinition : Integration/Feature/demo/demosteps.js

Note: Recommendation from team is to avoid using older way of having Global step definitions defined in cypress/support/step_definitions. More about the rationale for that is available in github documentation. We have specified to use latest style in package.json earlier.

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// Import Given , When, then from cypress-cucumber-preprocessort steps
import { Given, When, Then } from "cypress-cucumber-preprocessor/steps";

//Navigate to URl
const url = 'https://www.saucedemo.com/index.html'
Given('I open Demo shopping page', () => {
  cy.visit(url)
});

//Type in user name and password. Username is passed from feature file. For demo purpose password is hard coded
// We specify what is the type of variable in step ..See {string}
//Password is not logged by providing the option
When("I login as {string} user", (username) => {
    cy.get('#user-name').type(username);
    cy.get('#password').type('secret_sauce',{log:false});
    cy.get('#login-button').click();
  });


//Get list of children and assert its length
Then('I should see products listed', () => {
  cy.get('div.inventory_list').children().should('have.length', 6);
  });

Now run above demo file. This can be done in Cypress UI.

Result

Folder structure is as below FolderStructure

In the previous post we saw about working with Cookies in Cypress. Now let us look at how we can work with XHR request in Cypress.

XHR stands for XMLHttpRequest. It is an API in the form of an object whose methods transfer data between a web browser and a web server. Cypress provides inbuilt functionality to work with XHR request. It provides us with objects with information about request and response of these calls. It will help to do various assertions on header, url , body , status code etc as needed. It also help us to stub the response if needed.

In Cypress 5 , the XHR testing was done mainly using cy.server() and cy.route(). However they are deprecated in Cypress 6.0.0. In version 6, XHR testing can be done using cy.intercept(), which will help to manipulate behaviour of HTTP request made.

Usage format as defined in cypress documentation is as below

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cy.intercept(url, routeHandler?)
cy.intercept(method, url, routeHandler?)
cy.intercept(routeMatcher, routeHandler?)

As you can see in above, the last parameter is routeHandler , which defines what should happen if cypress is able to intercept a call matching initial parameters. We can specify the criteria as either a URL (either string or regular expression) , method (string) & url (string or regular exp) or various combinations using routeMatcher. RouteMatcher has a list of properties based on which we identify the network calls. Properties are like path, url, auth, headers etc. Cypress documentation has more details on this.

Now let us look at a practical example of asserting XHR. In below example,

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//below line is added to get intellisense in visual studio IDE
/// <reference types="cypress" />

it('Working with XHR In Cypress',() =>  {

    //I am using only one parameter for intercept , which is an object with property pathname. This is the third way above ( routeMatcher). Only possible chaining for intercept is an alias. Hence I assign an alias as 'weather' for the intercepted call

    cy.intercept({
        pathname: '/scripts/marketing.json'
    }).as('weather');

    //visit the webpage
    cy.visit("http://www.bom.gov.au/nsw/forecasts/sydney.shtml");

    //wait for the interception and once network calls are made, then proceed with remaining

    cy.wait('@weather').then((interception) => {
        // 'interception' is an object with properties 'id', 'request' and 'response'
        cy.log(interception.id);
        cy.log(interception.state);
        cy.log('Status code is ' + interception.response.statusCode);
        cy.log('response body is '+interception.response.body);

        expect(interception.response.statusCode).to.eq(200);
      })
})

Below is the results from running above test. As you can see the response body is an object.

result

Stubbing an XHR request

Now let us see how we can stub the response call. Add another parameter to intercept method , which matches the routeHandler.

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//below line is added to get intellisense in visual studio IDE
/// <reference types="cypress" />

it('Working with XHR In Cypress',() =>  {

    //Add second parameter to stub the response 
    cy.intercept({
        pathname: '/scripts/marketing.json'
    },'{ body: "Response body is stubbed" }').as('weather');
    cy.visit("http://www.bom.gov.au/nsw/forecasts/sydney.shtml");
    cy.wait('@weather').then((interception) => {
        // 'interception' is an object with properties 'id', 'request' and 'response'
        cy.log(interception.id);
        cy.log(interception.state);
        cy.log('Status code is ' + interception.response.statusCode);
        cy.log('response body is '+interception.response.body);

        expect(interception.response.statusCode).to.eq(200);
      })

})

Below is the results from running above test. As you can see the respone body is now having stubbed value passed above

result

Cypress has inbuild support to read browser cookies. There are two commands for this - GetCookie and GetCookies. Refer documentation for more details

GetCookie

This command get a cookie by its name.

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cy.getCookie(name)

cy.getCookie(name, options)

Note: name is the name of cookie . Options can be used to change default behaviour like logging , timeout

Examples usage is as below

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//Below line is added to get intellisense while writing code in visual studio code

/// <reference types="cypress" />


it('Read Cookies In Cypress',() =>  {

    cy.visit("www.commbank.com.au");

    //GetCookie returns an object with properties like name, domain, httpOnly, path, secure, value, expiry ( if provided), sameSite(if provided)

    //Checking for individual cookie property value
    cy.getCookie('s_cc').should('have.property','value','true');
    cy.getCookie('s_cc').should('have.property','domain','.commbank.com.au');


   // Checking multiple properties of a cookie. *cy.getCookie* will get an object. *Then* helps to work with object yielded from previous
    cy.getCookie('s_cc').then((cookie) => {

        cy.log(cookie);
        cy.log(cookie.name);
        expect(cookie.domain).to.equal('.commbank.com.au');
        expect(cookie.name).to.equal('s_cc');
        expect(cookie.httpOnly).to.equal(false);
        expect(cookie.path).to.equal('/');

        expect(cookie).to.not.have.property('expiry');
    })


})

Results from test run will look like below

result

Modifying environment variables for a logged in user is straight forward. However there are some instances when we need to modify environment variables for a different user. One frequent usage which I have come across is when we need to modify PATH variables for a service account in a CI box. Service account may not have local logon rights to the machine Or we may not know its password. Hence I always end up using below method to update path variables

Identify Security Identifier(SID)

Open command prompt and use below commands

Replace USERNAME with actual username

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wmic useraccount where name="USERNAME" get sid

We can also find username based on SID Replace SIDNUMBER with actual value

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wmic useraccount where sid="SIDNUMBER" get name

Once we have the SID number of the next user, move on to next step

Modify Registry

  • Open registry editore (Regedit.exe) in windows.
  • Navigate to HKEY_USERS >> SID of USER>> ENVIRONMENT
  • This should display all defined environment variables. We can modify all variables as we need

XML Schema Definition tool will help to generate classes that conform to a schema. Steps are as follows.

  • Open VS Command prompt . ( Start Menu >> Visual Studio 2019 >> Developer command prompt for VS2019)
  • Pass xml schema as an argument to xsd.exe . \c at the end denotes to generate classes

    xsd.exe C:\Temp\sampleschema.xsd /c /o:C:\Temp 
    
  • There are other options as well. Main ones are below.

    xsd.exe <schema.xsd> /classes|Dataset [/e:] [/l:] [/n:] [/o:] [/s:] 
    
    /classes | Dataset : denotes whether to generate class or dataset
    /e: Element from schema to process
    /l: Language to use for generated ode . Choose from 'CS','VB','JS','VJS','CPP'. Default is CS
    /n: Name os namespace
    /o: Output directory for generated classes
    
  • There are other options as well. Details can be found on help “xsd /?”

Location of xsd.exe tools is under C:\Program Files (x86)\Microsoft SDKs\Windows\\bin\NETFX Tools\xsd.exe. There are chances of having multiple versions of this tool . If you ever get “xsd is not recognised as n internal or external command” error, make sure the PATH variable is set to this. Else directly go to that location and run.

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  • Having a structured learning path
  • Having a mentor to guide and review the code.

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