JavaScript String substr() Method
Example
Extract parts of a string:
var str = "Hello world!";
var res = str.substr(1, 4);
The result of res will be:
ello
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More "Try it Yourself" examples below.
Definition and Usage
The substr() method extracts parts of a string, beginning at the character at the specified position, and returns the specified number of characters.
Tip: To extract characters from the end of the string, use a negative start number (This does not work in IE 8 and earlier).
Note: The substr() method does not change the original string.
Browser Support
| Method | |||||
|---|---|---|---|---|---|
| substr() | Yes | Yes | Yes | Yes | Yes |
Syntax
string.substr(start,length)
Parameter Values
| Parameter | Description |
|---|---|
| start | Required. The position where to start the extraction. First character is at index 0 |
| length | Optional. The number of characters to extract. If omitted, it extracts the rest of the string |
Technical Details
| Return Value: | A new String, containing the extracted part of the text. If length is 0 or negative, an empty string is returned |
|---|---|
| JavaScript Version: | 1.0 |
More Examples
Example
Begin the extraction at position 2, and extract the rest of the string:
var str = "Hello world!";
var res = str.substr(2);
The result of res will be:
llo world!
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Example
Extract only the first character:
var str = "Hello world!";
var res = str.substr(0, 1);
The result of res will be:
H
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Example
Extract only the last character:
var str = "Hello world!";
var res = str.substr(11, 1);
The result of res will be:
!
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JavaScript String Reference
