Getting started with the substr method of a JavaScript string object (used to intercept strings) _ basic knowledge

This article describes how to get started with the substr method of a JavaScript string object. substr is used to extract strings Based on the start position and length. For more information, see JavaScript substr Method

The substr method is used to intercept a string based on the start position and length and return part of the string. The syntax is as follows:

The Code is as follows:

Str_object.substr (start, length)

Parameter description:

Parameters	Description
Str_object	String (object) to be operated)
Start	Required. The position where the interception starts. The value starts from 0. If the value is negative, the value starts from the end of the string. (tested, some browser versions are invalid)
Length	Optional. The length of the string to be truncated. If this parameter is omitted, the string ends.

Tip: The substr method does not comply with the ECMAscript standard, so it is not recommended.

Substr Method Instance

The Code is as follows: