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 some other characters 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 pattern to replace. <br>Note that if this value is a string, it is treated as a literal text pattern to search for, rather than being converted to a RegExp object first. |
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);
};