Ajax synchronous sending and string truncation by step

Ajax synchronous transmission:

(1) Use of closures

Multiple Ajax requests are synchronously sent. (How many Ajax requests can be synchronously sent? Let the browser decide on its own). synchronous transmission, each ajax request handles its own request separately.

For (var I = 0; I <len; I ++ ){

Ajax. post (url, param, function (param, I ){

Return function (txt ){

Var res = txt. evalExp (); // parse the returned json object

// Here I can be used to process every ajax request

}

} (Param, I ));

}

(2) queue

Ps: the connection cannot be found. Tragedy ~

Function Buffer (handler ){

Var queue = [];

 

Function run (){

Var callback = function (){

If (queue. length> 0 ){

Run ();

}

}

Handler (queue. shift (), callback );

}

This. append = function (task ){

Queue. push (task );

 

If (queue. length = 1 ){

Run ();

}

 

}

}

 

Function Task (item, url, callback ){

This. item = item;

This. url = url;

This. callback = callback

}

 

Function taskHandler (task, callback ){

Ajax. post (task. url, task. item, function (txt ){

If (task. callback ){

Task. callback (txt );

}

Callback (txt );

});

}

Var buffer = new Buffer (taskHandler );

 

Operation:

Buffer. append (new Task (ajaxParams [I], ajaxURL [I], ajaxCallback [I]); // parameter, url, callback

String truncation by step

In fact, just use the function directly. Do not use prototype.

In addition:

Chinese characters are particularly difficult to handle,

When Step is 1, all are separated.

When Step is an odd number (3, 5 ...), The steps are separated. For example, the example above is divided