本文实例讲述了JavaScript判断数组是否包含指定元素的方法。分享给大家供大家参考。具体如下：

这段代码通过prototype定义了数组方法，这样就可以在任意数组调用contains方法

/** * Array.prototype.[method name] allows you to define/overwrite an objects method * needle is the item you are searching for * this is a special variable that refers to "this" instance of an Array. * returns true if needle is in the array, and false otherwise */Array.prototype.contains = function ( needle ) {  for (i in this) {    if (this[i] == needle) return true;  }  return false;}

用法：

// Now you can do things like:var x = Array();if (x.contains('foo')) {  // do something special}

希望本文所述对大家的javascript程序设计有所帮助。