javascript - AJAX响应后如何退出父函数

Question

这个问题已经有答案了:

How do I return the response from an asynchronous call? (42 个回答)

已关闭 10 年前。

我正在使用 AJAX 请求来检查某些内容是真还是假。以下是包括 AJAX 请求的完整功能:

function selectAnswer(id, questionId) {
    $.get("php/forms/select-answer-process.php?scope=get&id="+questionId, function(data) { if (data == "true") { alert("You can only select one answer per question"); } });

    var confirmChoice = confirm("Are you sure you want to select this as the correct answer? This cannot be undone.");
    if (confirmChoice) {
        $.get("php/forms/select-answer-process.php?scope=save&id="+id);
        document.getElementById("answer-check-"+id).src = "img/icons/check-green.png";
    } else {
        return false;
    }
}

警报效果很好，但如果 AJAX 响应为 true，我想退出父函数。我怎样才能做到这一点？

Answer 1

由于 ajax 是异步的，ajax 调用之后的任何内容仍然会在 ajax 调用完成后执行。相反，通常在 ajax 返回后使用回调来使用返回的数据。您应该在回调中使用从 ajax 调用返回的数据，如下所示:

function selectAnswer(id, questionId) {
 $.get("php/forms/select-answer-process.php?scope=get&id="+questionId, function(data) {
  if (data == "true") { 
   alert("You can only select one answer per question"); 
  }else{
   successResponse(id);//callback when ajax is complete
  }
 });
}

//function to be called if ajax completion is successful and correct
function successResponse(id){
 var confirmChoice = confirm("Are you sure you want to select this as the correct answer? This cannot be undone.");
 if (confirmChoice) {
    $.get("php/forms/select-answer-process.php?scope=save&id="+id);
    document.getElementById("answer-check-"+id).src = "img/icons/check-green.png";
 }
}