• 原理就是把pending状态时的res存入全局变量中,pending过程时对这些res进行选择性abort
• 感觉比单独设置一个flag方便,且适应型广

当只需要最后一次ajax

window.pendingRequests = {};
$.ajaxPrefilter(function (options, originalOptions, jqXHR) {
    var key = options.url+Math.random();
    if (!pendingRequests[key] && key.indexOf('.html') == -1) {
        pendingRequests[key] =jqXHR;       
    }
    for(let i in pendingRequests)
        if(i!=key){
            pendingRequests[i].abort()
        }
    var complete = options.complete;
    options.complete = function (jqXHR, textStatus) {
        delete pendingRequests[key];
        if ($.isFunction(complete)) {
            complete.apply(this, arguments);
        }
    };
});

当只需要第一次ajax

window.pendingRequests = {};
$.ajaxPrefilter(function (options, originalOptions, jqXHR) {
    var key=options.url;
    if (!pendingRequests[key] && key.indexOf('.html') == -1) {
        pendingRequests[key] =jqXHR;
    } else if (key.indexOf('.html') == -1) {
        jqXHR.abort();
    }
    var complete = options.complete;
    options.complete = function (jqXHR, textStatus) {
        delete pendingRequests[key];
        if ($.isFunction(complete)) {
            complete.apply(this, arguments);
        }
    };
});

同时执行多个不同api接口的且需要各自的最后一次时的ajax

window.pendingRequests = {};
$.ajaxPrefilter(function (options, originalOptions, jqXHR) {

    var key=options.url
    if (!pendingRequests[key] && key.indexOf('.html') == -1) {
        console.log(false)
        pendingRequests[key]=[]
        pendingRequests[key].push(jqXHR)
    }else{
        console.log(true)
        pendingRequests[key].push(jqXHR)
    }
    for(let i in pendingRequests){
        let len=pendingRequests[i].length

        for(let j=0;j<len-1;j++){
            pendingRequests[i][j].abort()
        }
    }
    setTimeout(function () {
        var complete = options.complete;
        options.complete = function (jqXHR, textStatus) {
            delete pendingRequests[key];
            if ($.isFunction(complete)) {
                complete.apply(this, arguments);
            }
        };
    },0)
});