JavaScript string Object substring method Getting started instance (for intercepting strings) _ Basics

JavaScript substring method

The substring method is used to intercept a string by specifying a start and end position and to return an intercept part of the string. The syntax is as follows:

Copy Code code as follows:

Str_object.substring (start, end)

Parameters	Description
Str_object	The string to manipulate (object)
Start	Necessary. Start intercept position, nonnegative integer
End	Optional. The position of the end of the string interception, a nonnegative integer, or, if omitted, until the end of the string

Tip: If the parameter start is equal to end, then the method returns an empty string. If start is larger than end, the method exchanges the two parameters before intercepting the string.

Substring Method Instance

Copy Code code as follows:

<script language= "JavaScript" >

var str = "ABCdef";
document.write (str.substring (1, 3) + "<br/>");
document.write (Str.substring (2, 2) + "<br/>");
document.write (Str.substring (3, 1));

</script>

Run this example, output:

Copy Code code as follows:

Bc

Bc

The difference between substring and slice and substr

The 1.substring cannot accept negative parameters, and the slice method can
2.substring The second parameter is the position at which the end of the interception is specified, and the second parameter of the Substr method is the length of the specified string interception