Question

当满足两个条件时，我需要执行特定的函数mvFinishItUp()。更具体地说，一个条件是$.ajax的回调成功，另一个条件是代码的正常流程，直到它到达函数。有点：

$.ajax({
    url: mv_finalUrl,
    success: function (data) {
        mvFinishItUp(data);
    },
    dataType: 'html'
});

/* here a lot more code, with animations and some delays */

mvFinishItUp(data) {
    /* My function code */
    /* But this code must only run after it has been called via the call back
       and after all the other code has been ran as well */
}

因此，如果ajax回调更快，或者相反，该函数必须等待所有代码。关于如何实施这一点的任何想法？

我愿意改变脚本代码的整个概念，因为我相信ajax和函数本身之间的松散代码应该转到函数中......

Answer 1

这是jQuery Deferred objects的完美用例。

从AJAX调用中删除success:参数，稍后注册处理程序：

var jqxhr = $.ajax(...); 

// do some other synchronous stuff
...

// and *then* register the callback
jqxhr.done(mvFinishItUp);

延迟对象在（事件已经完成事件之后）在AJAX事件上注册时，完美地（按设计）处理。

Answer 2

这里我添加了第二个参数来检查回调检查

 function mvFinishItUp(data, byCallback) {

    var iscallback = byCallback || false; // if you don't send byCallback
                                          // default will false
    if(iscallback) {
       // execute if called by callback
    }
 }

 success: function (data) {
        mvFinishItUp(data, true); // call with second parameter true
 },

要在完成ajax并执行ajax和mvFinishItUp()之间的所有代码后执行mvFinishItUp，您可以执行以下操作：

var allFunctionExecuted = false; // global to detect all code execution

$.ajax({
    url: mv_finalUrl,
    success: function (data) {
        mvFinishItUp(data, true);
    },
    dataType: 'html'
});

function func1() {

}

function func2() {

}

// some other code

function func3() {
    allFunctionExecuted = true;
}

现在，

 function mvFinishItUp(data, byCallback) {

    var iscallback = byCallback || false; // if you don't send byCallback
                                          // default will false

    if(iscallback && allFunctionExecuted) {

       // execute if ajax done
       // and others code done
    }
 }

Answer 3

也许这样的事情可以解决问题：

var _data = undefined;

$.ajax({
    url: mv_finalUrl,
    success: function (data) {
        _data = data;
        myFinishItUp(data); // call the function from here if it's faster
    },
    dataType: 'html'
});

/* here a lot more code, with animations and some delays */

function myFinishItUp(data) {
    this.data = data; // store the data from the AJAX call or the code, whichever reaches first 
                      // if the code reaches this before the AJAX call completes, data will be undefined
    if(typeof this.wasCalled == "undefined") {
        /* My function code */
        /* But this code must only run after it has been called via the call back
           and after all the other code has been ran as well */
        this.wasCalled = true;
    }
}(_data); // function that calls itself when the code gets to this point with a self-contained boolean variable to keep track of whether it has already been called

当代码流到达那一点时，我使用了一个自调用函数execute，但是如果它是从AJAX调用中调用的，它就不会执行。它会跟踪是否已使用自包含的布尔值调用它。

Answer 4

尝试如下，（这只是伪代码）

var isAJAXDone = false, isFunctionCodeDone = false;
$.ajax({
  //..
  success: function () {
     isAJAXDone = true;
     mvFinishItUp(data, isAJAXDone, isFunctionCodeDone);
  } 
});

//..Your function code
//..Add this below the last line before the function ends
isFunctionCodeDone = true;
mvFinishItUp(data, isAJAXDone, isFunctionCodeDone);


//..
mvFinishItUp(data, isAJAXDone, isFunctionCodeDone ) {
   if (isAJAXDone && isFunctionCodeDone) {
      //Do your magic
   }
}

Answer 5

这是非常“丑陋”的代码，但您可以将其修改为不使用全局变量，所以这只是说明性的：

var ajaxExecuted = false,
    codeExecuted = false;

$.ajax({
    url: mv_finalUrl,
    success: function (data) {
        ajaxExecuted = true;
        mvFinishItUp(data);
    },
    dataType: 'html'
});

/* here a lot more code, with animations and some delays */
codeExecuted = true;

mvFinishItUp(data) {
    /* My function code */
    if(ajaxExecuted && codeExecuted) {
      /* But this code must only run after it has been called via the call back
         and after all the other code has been ran as well */
    }
}

我刚刚添加了两个标志：ajaxExecuted和codeExecuted，并在函数内部有一个if语句，用于检查这些标志的值，并仅在其中两个标志设置为true时执行。所以没有mather首先调用它，只有在两个标志设置为true时才会执行。

更简洁的方法可能是在对象中实现该函数，并使用属性而不是全局变量。

当满足两个条件时，jquery执行函数

5 个答案: