Typescript + Jquery Ajax +这个

Question

我将一些javascript代码移植到打字稿上,我遇到了一个问题.

我有一个ajax调用,它将一个对象作为上下文传递,该对象包含一些回调和一些其他信息,这些信息由成功或错误回调读出,指示成功调用应该重定向到的位置:

function SomeAjaxService
{
    var self = this;

    self.CheckErrorType = function(...) {
        // Do something
    };

    var SuccessProxyCallback = function(results) {
        // Do some stuff with results, like send off some events
        this.successCallback(results);
    };

    var FailureProxyCallback = function(...) {
        // Do some stuff with errors, and fire some events
        var someErrorType = self.CheckErrorType(...);
        this.failureCallback(someErrorType);        
    };

    self.SendRequest = function(requestArgs) {
        var ajaxSettings = {
            context: requestArgs,
            // Assign a load of stuff
        };

        $.ajax(ajaxSettings);
    };
}

现在您可以看到失败代理调用本地方法以及使用"this"上下文对象.那你怎么用打字稿来处理这种情况呢？

你可以self = this在构造函数中设置并继续像以前一样吗？

==编辑==

这里要求的是上面的类表示,显示由于缺少自变量,这需要两件事.

class SomeAjaxService
{
    public CheckErrorType(someArg1: any, someArg2: any) {
        // Do some stuff with data
    };

    private SuccessProxyCallback(results: any) {
        // Do some stuff with results, like send off some events
        this.successCallback(results); 

        // Does the above *THIS* usage point to the context of the 
        // Ajax call or the actual instantiated class
    };

    private FailureProxyCallback(...) {
        // Do some stuff with errors, and fire some events
        var someErrorType = this.CheckErrorType(...);

        // The above *THIS* call cannot be correct if the context has overwritten
        // the scope of this, however I dont know if this is true, do I even need
        // this.CheckErrorType to invoke a local method?

        this.failureCallback(someErrorType);        

        // As mentioned above same issue here but the *THIS* should hopefully
        // point to the context object on the ajax object not the local instance.
    };

    public SendRequest(requestArgs: any) {
        var ajaxSettings : JqueryAjaxSettings = {
            context: requestArgs,
            // Assign a load of stuff
        };

        $.ajax(ajaxSettings);
    };
}

就像我上面说的那样,主要问题是在一个方法中我需要调用其中一个实例方法,并从ajax调用中调用上下文对象上的方法.使用原始的javascript我会有self = this,然后我可以绕过this被覆盖,这是在范围内保持ajax异步状态对象所必需的.

Answer 1

你能在构造函数中设置self = this并继续像以前一样吗？

抽象地说,在构造函数中执行此操作通常不会解决任何问题(除非您稍后在该方法中捕获它 - 请参阅下文).TypeScript类在对象本身上存储类实例数据,而不是捕获本地.因为self将存储在this对象上,所以您最终不会拥有之前没有的任何内容.

这是一种方法:

class SomeAjaxService
{
    private FailureProxyCallback(context, arg) {
        // now 'this' is the class instance and 'context' is requestArgs 
    }

    public SendRequest(requestArgs) {
        var self = this; // Note: captured local used in closure below
        var ajaxSettings = {
            context: requestArgs,
            // Do not use an arrow function here, even though it's tempting!
            error: function(arg) { self.FailureProxyCallback(this, arg) }
        };

        $.ajax(ajaxSettings);
    };
}