实时汇率获取 解决跨域以及循环Ajax请求

前端框架 ExtJs

//币种代码
var currencys = [
    {curCode: 'USD'},
    {curCode: 'CNY'},
    {curCode: 'HKD'},
];
setInterval(function () {
    for (var idx = 0, len = currencys.length; idx < len; idx++) {
        for (var itx = 0, len2 = currencys.length; itx < len2; itx++) {
            let scur = currencys[idx].curCode;
            let tcur = currencys[itx].curCode;
            if (scur == tcur) continue;
            //测试url次数有限
            let url = 'http://api.k780.com:88/?app=finance.rate&' +
                'scur=' + scur + '&tcur=' + tcur + '&appkey=10003&sign=b59bc3ef6191eb9f747dd4e83c99f2a4'
            console.info(url);
            Ext.Ajax.request({
                url: url,//这里是填写需要跨域访问的URL
                cors: true,
                useDefaultXhrHeader: false,
                method: 'get',
                //async: false,//可开启同步
                headers: {
                    "Origin:": 'http://api.k780.com',//这里是填写需要跨域访问的URL Origin字段用来说明，本次请求来自哪个源
                    "Access-Control-Allow-Origin": 'http://api.k780.com',//这里是填写需要跨域访问的URL
                    "Access-Control-Allow-Credentials": true,
                    "Content-Type": 'application/json'  //文件上传的格式，
                },
                success: function (res, opts) {
                    var text = res.responseText;
                    //{"success":"1","result":{"status":"ALREADY","scur":"USD","tcur":"CNY","ratenm":"美元/人民币","rate":"7.0677","update":"2019-12-04 10:14:04"}}
                    console.info(text);
                },
            });
        }
    }
}, 60 * 60 * 1000);

参考 EXTJS 使用Ajax跨域上传文件​​​​​​​