OnLoad loading multiple function instances in JavaScript

If you assign a value directly to Winow.onload, the OnLoad event that was originally bound is overwritten. How to bind more than once, there are three ways
1. Write the event you want to bind, and then assign the onload

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Window.onload=function () {function1 (); function2 ();}

2, through the custom addloadevent to solve

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function Addloadevent (func) { var oldonload=window.onload; if (typeof window.onload!= ' function ') { Window.onload=func; }else{ Window.onload=function () { Oldonload (); Func (); } } }

To add an event to load execution:

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Addloadevent (FUNC1); Addloadevent (FUNC2);

3, if you want to give an event in your program to assign a number of processes, as long as the first judge the browser, and then according to different browsers, choose to use Attachevent or addeventlistener on it. Examples are as follows

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if (document.all) { Window.attachevent (' onload ', func1); Window.attachevent (' onload ', FUNC2); } else { Window.addeventlistener (' Load ', func1, false); Window.addeventlistener (' Load ', FUNC2, false); }

Is there any other way besides the above method?

Usage is as follows:

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function func () {alert ("This is window onload event!"); return;} Window.onload=func; Or as follows: Window.onload=function () {alert ("This is window onload event!"); return;}

However, window.onload cannot load multiple functions at the same time.

Like what:

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function T () { Alert ("T") } Function B () { Alert ("B") } Window.onload =t; Window.onload =b;

The previous overlay will be followed, and the above code will only output B.
The following methods can be used to resolve this:

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Window.onload =function () {t (); b (); }

Another solution

Code

The code is as follows

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Code highlighting produced by Actipro Codehighlighter (freeware) http://www. codehighlighter.com/--> function Addloadevent (func) { var oldonload = window.onload;//to get the last onload event function if (typeof window.onload!= ' function ') {//To determine whether the type is ' function ', note that TypeOf returns a string Window.onload = func; } else { Window.onload = function () { Oldonload ()//The function of the OnLoad event overridden before the call----> because I don't know much about JS, I'm temporarily aware of the idea of loading multiple functions by overwriting the onload function Func ()//Call Current event function } } } (complete example) uses the following: function T () { Alert ("T") } Function B () { Alert ("B") } Function C () { Alert ("C") } function Addloadevent (func) { var oldonload = window.onload; if (typeof window.onload!= ' function ') { Window.onload = func; } else { Window.onload = function () { Oldonload (); Func (); } } } Addloadevent (t); Addloadevent (b); Addloadevent (c); Equivalent to Window.onload =function () {t (); b (); C ();}

Individuals assume that implicit functions such as: Window.onload =function () {T () are directly used. b (); C ();}) Faster, of course, use addloadevent more professional, each take the good!

performing multiple window.onload produces too much recursion error

, the common solution is as follows :

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<script type= "Text/javascript" > var func = window.onload; Window.onload = function () { Func? Func (): 0; Alert (1); } </script>

The principle is to pass the Window.onload event one level at a time to ensure that every window.onload event can be executed, but if there are multiple calls and variable names, it will produce too much recursion error, as follows

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<script type= "Text/javascript" > var func = window.onload; Window.onload = function () { Func? Func (): 0; Alert (1); } func = window.onload; Window.onload = function () { Func? Func (): 0; Alert (2); } </script>

The above implementation executes two window.onload events, but because each pass window.onload event is defined as the same variable name, a too much recursion error is generated.

Solving method
The reason for this is that the definition of the same variable name produces loop execution code, so the solution needs to be resolved only by defining the variable name differently. As follows

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<script type= "Text/javascript" > var func = window.onload; Window.onload = function () { Func? Func (): 0; Alert (1); } func1 = window.onload; Window.onload = function () { Func1? Func1 (): 0; Alert (2); } </script>

If a Web page appears multiple Window.onload events, try to merge operations processing, or implement a jquery-like ready event mechanism to solve redundant code problems and improve the readability of your code.

For more details please see: http://www.111cn.net/wy/js-ajax/too-much-recursion.htm