Parse JSON string in Typescript

By Sidd Bhattacharjee -
Typescript is typed superset of Javascript. It has extension of .ts, it finally gets compiled to plain Java Script.

Here we will see how we can parse a string representing JSON data and map it to TypeScript Object.

Say the following is our UserDetails object



 export class UserDetails {



  name: string;



  firstName: string;



  lastName: string;



  sessionToken: string;



  roles: Array<string>;







  constructor(name?: string, firstName?:string, lastName?:string, sessionToken?: string) {



    this.name = name;



    this.firstName = firstName;



    this.lastName = lastName;



    this.sessionToken = sessionToken;



}









And the JSON string as follows,





{  



 "name":"Sidd",



 "firstName":"Sidd",



 "lastName":"Bhatt",



 "sessionToken":"d501dce2-a628-4e4c-9ea0-1b2ea31f5270",



 "rememberMe":false,



 "authenticated":true



}







Following code will parse the above string and create instance of UserDetails object.





let currentUserStr = "contains the above sample json string;



let userDetailsObject:UserDetails = JSON.parse(currentUserStr);



console.log("Session Token = " + userDetailsObject.sessionToken);















































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