JS determines whether a string is included with a string, and if the array contains an element;

Requirements: End A string does it contain another string?

Realize:

var str = "ADC";

Determine if STR contains "C"

if ( str.indexof ("C") >0) {

Alert ("str contains string C")

}

Requirements: End An array contains an element?

A JS prototype chain is needed:

The following code is to add the contains method to the array meaning: As long as the array will have this method

　　　　Array.prototype.contains = function ( needle ) {   　　　　 for (i in this ) {    　　　　  if ( this [i] == needle) return true ;   　　　　 }   　　　　 return false ; 　　　　}Usage: Example:
　　　　var x = Array();或var x = []; 　　　　if (x.contains( ‘foo‘ )) {   　　   // 包含foo做什么事情； 　　　　}

JS determines whether a string is included with a string, and if the array contains an element;