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目录

JavaScript String substring()

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Examples

Extract a substring from text:

let text = "Hello world!";
let result = text.substring(1, 4);
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Start from position 2:

let result = text.substring(2);
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More examples below.

Description

The substring() method extracts characters, between two indices (positions), from a string, and returns the substring.

The substring() method extracts characters from start to end (exclusive).

The substring() method does not change the original string.

If start is greater than end, arguments are swapped: (4, 1) = (1, 4).

Start or end values less than 0, are treated as 0.

See Also:

The split() Method

The slice() Method

The substr() Method

Syntax

string.substring( start, end)

Parameters

Parameter Description
start Required.
Start position.
First character is at index 0.
end Optional.
End position (up to, but not including).
If omitted: the rest of the string.

Return Value

Type Description
A string A string containing the extracted characters.

More Examples

If start is greater than end, parameters are swapped:

let result = text.substring(4, 1);
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If "start" is less than 0, it will start from index 0:

let result = text.substring(-3);
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Only the first:

let result = text.substring(0, 1);
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Only the last:

let result = text.substring(text.length - 1);
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Related Pages

JavaScript Strings

JavaScript String Methods

JavaScript String Search

Browser Support

substring() is an ECMAScript1 (ES1) feature.

ES1 (JavaScript 1997) is fully supported in all browsers:

Chrome Edge Firefox Safari Opera IE
Yes Yes Yes Yes Yes Yes
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