JavaScript replace() Method
Example
In this example, we will perform a replacement where the first occurrence of "Microsoft" is found and replaced with "tutorialpro":
var str = "Visit Microsoft! Visit Microsoft!";
var n = str.replace("Microsoft", "tutorialpro");
n Output:
Visit tutorialpro! Visit Microsoft!
Definition and Usage
The replace() method is used to replace some characters with others in a string, or to replace a substring that matches a regular expression.
For more information on regular expressions, please refer to our: RegExp Tutorial and RegExp Object Reference.
This method does not change the original string.
Browser Support
All major browsers support the replace() method.
Syntax
Parameter Values
| Parameter | Description |
|---|---|
| searchvalue | Required. Specifies the substring or the pattern to be replaced. <br>Note that if this value is a string, it is treated as a literal text pattern to be searched for, rather than being converted to a RegExp object. |
| newvalue | Required. A string value that specifies the replacement text or a function that generates the replacement text. |
Return Value
| Type | Description |
|---|---|
| String | A new string with the specified replacements made. |
Technical Details
| JavaScript Version: | 1.2 | | --- | --- |
More Examples
Example
Perform a global replacement:
var str = "Mr Blue has a blue house and a blue car";
var n = str.replace(/blue/g, "red");
n Output:
Mr Blue has a red house and a red car
Example
Perform a global replacement, ignoring case:
var str = "Mr Blue has a blue house and a blue car";
var n = str.replace(/blue/gi, "red");
n Output:
Mr red has a red house and a red car
Example
In this example, we add a method to JavaScript's String object prototype to replace all occurrences of "Microsoft" with "tutorialpro":
String.prototype.replaceAll = function(search, replacement) {
var target = this;
return target.replace(new RegExp(search, 'g'), replacement);
};