相关疑难解决方法(0)

如何从异步调用返回响应?

我有一个foo发出Ajax请求的函数.我怎样才能从中回复foo

我尝试从success回调中返回值,并将响应分配给函数内部的局部变量并返回该变量,但这些方法都没有实际返回响应.

function foo() {
    var result;

    $.ajax({
        url: '...',
        success: function(response) {
            result = response;
            // return response; // <- I tried that one as well
        }
    });

    return result;
}

var result = foo(); // It always ends up being `undefined`.
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javascript ajax jquery asynchronous xmlhttprequest

5208
推荐指数
38
解决办法
134万
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如何以及何时使用'async'和'await'

从我的理解主要事情之一asyncawait要做的就是让代码易于读写-但使用它们等于产卵后台线程来执行持续时间长的逻辑?

我正在尝试最基本的例子.我在内联添加了一些评论.你能为我澄清一下吗?

// I don't understand why this method must be marked as `async`.
private async void button1_Click(object sender, EventArgs e)
{
    Task<int> access = DoSomethingAsync();
    // task independent stuff here

    // this line is reached after the 5 seconds sleep from 
    // DoSomethingAsync() method. Shouldn't it be reached immediately? 
    int a = 1; 

    // from my understanding the waiting should be done here.
    int x = await access; 
}

async Task<int> DoSomethingAsync()
{
    // is …
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.net c# asynchronous async-await

989
推荐指数
19
解决办法
78万
查看次数