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1. js Array loop traversal. array loop variable, the first thing to think about is the for (Var i=0;i<count;i++) way.
In addition, you can use a simpler foreach method
2. The ForEach function.
Both Firefox and Chrome's array types have foreach functions. Use the following:
<!--Add by oscar999-->
<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 transitional//en" >
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<meta name= "Author" content= "oscar999" >
</HEAD>
<BODY>
<script>
var arryall = [];
Arryall.push (1);
Arryall.push (2);
Arryall.push (3);
Arryall.push (4);
Arryall.foreach (function (e) {
alert (e);
})
</script>
</BODY>
</HTML>But above, the code does not work correctly in IE.
Because IE's array does not have this method
The execution of the above sentence is "undefined", which means that the Array in IE does not have a foreach method.alert (Array.prototype.forEach);
3. Make IE compatible with foreach method
Since IE's array does not have a foreach method, we will manually add this prototype method to it.
Array.foreach implementation for IE support.
Https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/forEach
if (! Array.prototype.forEach) {
Array.prototype.forEach = function (callback, thisarg) {
var T, K;
if (this = = null) {
throw new TypeError ("This is null or not defined");
}
var O = Object (this);
var len = o.length >>> 0; Hack to convert O.length to a UInt32
if ({}.tostring.call (callback)!= "[Object Function]") {
throw new Typee Rror (callback + "is not a function");
}
if (thisarg) {
T = Thisarg;
}
k = 0;
while (K < Len) {
var kvalue;
if (k in O) {
kvalue = o[k];
Callback.call (T, Kvalue, K, O);
}
k++;}}
<!--Add by oscar999--> <! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 transitional//en" > <HTML> <HEAD> <TITLE> New Document </ title> <meta name= "Author" content= "oscar999" > </HEAD> <BODY> <script> if (!
Array.prototype.forEach) {Array.prototype.forEach = function (callback, thisarg) {var T, K;
if (this = = null) {throw new TypeError ("This is null or not defined");
var O = Object (this); var len = o.length >>> 0; Hack to convert O.length to a UInt32 if ({}.tostring.call (callback)!= "[Object Function]") {throw new TypeError (
Callback + "is not a function");
} if (thisarg) {T = Thisarg;
} k = 0;
while (K < Len) {var kvalue;
if (k in O) {kvalue = o[k];
Callback.call (T, Kvalue, K, O);
} k++;
}
};
} var arryall = [];
Arryall.push (1);
Arryall.push (2);
Arryall.push (3);
Arryall.push (4);
Arryall.push (5);
var arryspecial = []; Arryall.foreach (function (e) {if (e)%2==0) {Arryspecial.push (e);
}else if (e%3==0) {Arryspecial.push (e);
}) </script> </BODY> </HTML>
Arryall.foreach (function (e) {
if (e%2==0)
{
arryspecial.push (e);
return;
}
if (e%3==0)
{
arryspecial.push (e);
return;
}
})As for how to write the effect of similar break, there is no better way to find out.
There is a search, some say return false can be reached, tried, the effect and return and return ture is the same.
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