JS Intercept and split string

Substr method

Returns a substring of the specified length starting at the specified position.

Stringvar.substr (start [, length])

Start: Required option. The starting position of the desired substring. The index of the first character in the string is 0.

Length: Optional. The number of characters that should be included in the returned substring.

Description: If length is 0 or negative, an empty string is returned. If this argument is not specified, the substring continues to the end of the stringvar.

Example:

function SubstrDemo(){    var s, ss;        // 声明变量。    var s = "The rain in Spain falls mainly in the plain." ;    ss = s.substr(12, 5); // 获取子字符串。    return (ss);        // 返回 "Spain"。 }

Substring method

Returns a substring at the specified position in a string object.

Strvariable.substring (start, end)
"String Literal". Substring (start, end)

Parameters

Start: Indicates the starting position of the substring starting at 0.

End: Indicates the ending position of the substring, starting at 0.

Description

The substring method Returns a string containing a substring from start to last (without end).

The substring method uses the smaller values from start and end as the starting point for the substring. For example, strvar.substring (0, 3) and strvar.substring (3, 0) will return the same substring.

If start or end is NaN or negative, replace it with 0.

The length of the substring equals the absolute value of the difference between start and end. For example, the length of the substring returned in strvar.substring (0, 3) and strvar.substring (3, 0) is 3.

Example:

function SubstringDemo(){    var ss; // 声明变量。    var s = "The rain in Spain falls mainly in the plain.." ;    ss = s.substring(12, 17); // 取子字符串。    return (ss); // 返回子字符串。 }

Function: IndexOf ()

Function: Returns the subscript of the first character of a matched substring in a string

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var myString="JavaScript";var w=myString.indexOf("v");w will be 2var x=myString.indexOf("S");x will be 4var y=myString.indexOf("Script");y will also be 4var z=myString.indexOf("key");z will be -1

Reference: http://www.jb51.net/article/74614.htm

js Intercept and split string