How to use jQuery setTimeout() function_jquery

setTimeout()
Delay the specified time from loading to execute an expression or function;
Execute only once; used together with window.clearTimeout.

I Copy the code in

The code is as follows:

$(document).ready(function (){
setTimout(test(),200);
function test()
{
alert(1);
}
});

will only be executed once. Some friends said that you can use

Copy the code The code is as follows:

setInterval ("showTime()", 5000);
function showTime()
{
var today = new Date();
alert("The time is: " today.toString ());
}

But I can also call the following method the same as setInterval

Copy code The code is as follows:

Several ways to use setTimeout in jQuery

setTimeout/setInterval in jQuery cannot be used like in the original javascript, otherwise an error will be reported.

Let's use examples to illustrate several ways to use setTimeout in jQuery. First, prepare the DIV and public functions for testing:

Copy code The code is as follows:

The basic usage of setTimeout in original javascript is like this.

Copy code The code is as follows:

//Basic usage of setTimeout in original javascript
functionfunA(){
log('funA.. .');
setTimeout('funA()', 1000);
}
funA();

The following are several uses of setTimeout in jQuery Method. Online example

Copy code The code is as follows:

//Usage in jQuery
functionfunA(){
log('funA...');
setTimeout('funA()', 1000);
}

jQuery(document).ready(function($){
//Usage 1: Write the function to be called outside ready, making it a global function
funA();

//Usage 2: Write the function name directly, without brackets or quotes, suitable for functions without parameters
functionfunB(){
log('funB...');
setTimeout(funB, 1000);
}
funB();

//Usage 3: Executed by calling an anonymous function, suitable for functions with parameters
functionfunC(v){
log('funC...' v);
setTimeout(function(){funC(v 1)}, 1000);
}
funC(1);

//Usage 4: By adding functions to the jQuery namespace, the scope of application is wider
$.extend({
funD:function(v){
log('funD...' v) ;
setTimeout("$.funD(" (v 1) ")",1000);
}
});
$.funD(100);
});

The difference between Usage 2 and Usage 3 is obvious, but what is the difference between Usage 3 and Usage 4? Why is Usage 4 more widely applicable than Usage 3? Take the following example You can intuitively understand the difference between the two:

Copy the code The code is as follows:

jQuery(document).ready(function($){
//Usage 3: Executed by calling an anonymous function, suitable for functions with parameters
functionfunC(v){
log('funC. ..' v);
setTimeout(function(){funC(v 1)}, 1000);
}

//Usage 4: By adding a function to the jQuery namespace, call It is more convenient
$.extend({
funD:function(v){
log('funD...' v);
setTimeout("$.funD(" (v 1) ")",1000);
}
});
});

jQuery(document).ready(function($){
//funC(1) ; //When executing this sentence after removing the comment, an error will be reported
$.funD(100); //This sentence is normal, understand the difference between the two
});