Ajax 中的异常处理

Question

我正在从我的 HTTPS 页面进行以下 ajax 调用，

 $.ajax({
    url: "http://www.w3schools.com",
    dataType: 'jsonp',
    crossDomain: true,
    complete: function (e, xhr, settings) {
        switch (e.status) {
            case 200:
                //everything fine
                break;
            default: 
                //Somethings wrong, show error msg                                   
                break;
        }
    }
});

但由于我是从 HTTPS 页面进行 HTTP 调用，所以调用被阻止。 我可以在控制台（CHROME）中看到“不安全的内容警告”，

但是在完成、错误或成功中都没有捕获到错误。他们根本不开火。

我需要捕捉错误。 有什么办法可以做到这一点？

Answer 1

 error
    Type: Function( jqXHR jqXHR, String textStatus, String errorThrown )

A function to be called if the request fails. The function receives three arguments: The 

jqXHR (in jQuery 1.4.x, XMLHttpRequest) object, a string describing the type of error that 

occurred and an optional exception object, if one occurred. Possible values for the second 

argument (besides null) are "timeout", "error", "abort", and "parsererror". When an HTTP 

error occurs, errorThrown receives the textual portion of the HTTP status, such as "Not 

Found" or "Internal Server Error." As of jQuery 1.5, the error setting can accept an array 

of functions. Each function will be called in turn. Note: This handler is not called for 

cross-domain script and cross-domain JSONP requests. This is an [Ajax Event][1].

试试这个，

使用jqXHR.status查找请求状态

Demo

$.ajax({
    url: "http://www.w3schools.com",
    dataType: 'jsonp',
    crossDomain: true,
    complete: function (e, xhr, settings) {
        switch (e.status) {
            case 200:
                //everything fine
                break;
            default: 
                //Somethings wrong, show error msg                                   
                break;
        }
    },
    error: function(jqXHR, textStatus, errorThrown){

    alert(errorThrown)
    },
});