jquery - ajax异步: true statement execution order

Question

我有以下Ajax，我想知道异步Ajax调用的回调方法何时开始执行。

statement 1;
statement 2;
statement 3;
statement 4;
statement 5;
jQuery.ajax({
    url: "/includes/unit.jsp?" + params,
    cache: false,
    dataType: "html",
    async: true,
    success: function (html) {
        statement 6;
        statement 7;
    }
});
statement 8;
statement 9;
statement 10;
statement 11;
    .
    .
    .
statement 10000;  

我知道语句 1 到语句 5 将按顺序执行。由于 async: true，statement 8; 接下来将执行，我的问题是

when will statement 6; and statement 7; execute, will it execute all the statements after the ajax call till statement 10000 then execute success method. or at some point it got the response from server while executing statement 500, execute success method then start executing statement 501??

Answer 1

首先，async: true是默认的，不需要指定。一旦 ajax 请求返回成功响应，语句 6 将立即执行。这取决于很多因素，需要多少时间。语句 7 将在语句 6 之后立即执行。