TypeScript | String replace() Method

The replace() is an inbuilt function in TypeScript which is used to find a match between a regular expression and a string, and replaces the matched substring with a new substring. 
Syntax:

string.replace(regexp/substr, newSubStr/function[, flags]);

Parameter: This method accept five parameter as mentioned above and described below: 

• regexp: This parameter is a RegExp object.
• substr: This parameter is a String that is to be replaced.
• newSubStr: This parameter is a String that replaces the substring.
• function: This parameter is a function to be invoked to create the new substring.
• flags: This parameter is a String containing any combination of the RegExp flags.

Return Value: This method returns a new changed string. 

Below example illustrate the  String replace() method in TypeScriptJS:

Example 1:

JavaScript

<script>
    // Original strings
    var str = "Geeksforgeeks - Good Platform";

    var re = /Good/gi;

    // Use of String replace() Method
    var newstr = str.replace(re, "Best");
    console.log(newstr);
</script>

Output:

Geeksforgeeks - Best Platform

Example 2:

JavaScript

<script>
    // Original strings
    var str = "Geeksforgeeks TypeScript";

    var re = /(\w+)\s(\w+)/;

    // use of String replace() Method
    var newstr = str.replace(re, "$2 $1");
    console.log(newstr);
</script>

Output:

TypeScript Geeksforgeeks