JavaScript indexOf()Method
JavaScript String ObjectExample
Find the string "welcome":
var str="Hello world, welcome to the universe.";
var n=str.indexOf("welcome");
var n=str.indexOf("welcome");
nOutput result:
Try it yourself »
Definition and Usage
The indexOf() method returns the position of the first occurrence of a specified string value in a string.
If no matching string is found, -1 is returned.
Note:The indexOf() method is case-sensitive.
Tip:You can also check out similar methodslastIndexOf() 。
Browser Support
All major browsers support the indexOf() method.
Syntax
string.indexOf(searchvalue,start)
Parameter Values
| Parameter | Description |
|---|---|
| searchvalue | Required. Specifies the string value to be retrieved. |
| start | Optional integer parameter. Specifies the position in the string to start the search. Its legal values are 0 to string Object.length - 1. If this parameter is omitted, the search will start from the first character of the string. |
Return Value
| Type | Description |
|---|---|
| Number | The position of the first occurrence of the specified string, or -1 if no matching string is found. |
Technical Details
| JavaScript Version: | 1.0 |
|---|
More Examples
Example
Find the first occurrence of the character "e" in the string:
var str="Hello world, welcome to the universe.";
var n=str.indexOf("e");
var n=str.indexOf("e");
nOutput result:
Try it yourself »
Example
Start searching for the first occurrence of the character "e" from the fifth position in the string:
var str="Hello world, welcome to the universe.";
var n=str.indexOf("e",5);
var n=str.indexOf("e",5);
nOutput result:
Try it yourself »
Other Extensions