基于promise和script标签的jsonp

function Jsonp(url){
   var url=url.indexOf('?')>-1?url+"&callback=callback":url+"?callback=callback";
    return new Promise(function(resolve,reject){
        var script=document.createElement('script');
        script.src=url
        document.head.appendChild(script);
        window.callback=function(param){
            resolve(param)
        }
    })
}
//后台返回数据示例：callback({'name':'liuhao'})
Jsonp("http://192.168.1.100:2015/").then(function(res){
    console.log(res)//{'name':'liuhao'}
})