ajax的重写

$.najax = function (options) {
    var opts = $.extend({
        alerterror: false, alertbierror: false, cache: false, dataType: "json"
    }, options);
    opts.success = function (data) {
        $.loading(false);
        if (options.success) {
            options.success(data);
        }
    }
    opts.error = function () {
        $.loading(false);
        if (options.error) {
            options.error();
        }
    }
    opts.beforeSend = function () {
        $.loading(true);
    };
    opts.complete = function () {
        $.loading(false);
        if (options.complete) {
            options.complete();
        }
    };
    $.ajax(opts);
}
//loading效果
$.loading = function (bool) {
    if (bool) {
        document.getElementById("load").style.display = "";//显示等待效果
        document.getElementById("load").style.cursor = "wait";//鼠标开始等待
    } else {
        document.getElementById("load").style.display = "none";//结束等待效果
        document.getElementById("load").style.cursor = "default";//鼠标停止等待
    }
}