Getting started with the substr method of JavaScript string objects (used to intercept strings)_Basic knowledge

JavaScript substr method

The

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

Copy code The code is as follows:

str_object.substr(start, length)

Parameter description:

参数	说明
str_object	要操作的字符串（对象）
start	必需。开始截取的位置，从 0 开始计算；如果为负数则从字符串末尾开始计算（经测试，某些浏览器版本下无效）
length	可选。指要截取的字符串长度，省略则至到字符串结束

Tip: The substr method does not comply with the ECMAscript standard and is therefore not recommended.

substr method instance

Copy code The code is as follows:

Run this example, output: jb51

Copy code The code is as follows:

jb51