Ajax 异步传输应用

??最近在工作中接触了异步传输，现在总结一下。

之前用的比较多的，也是比较普遍的是js最基本的调用

function verify(){var userName = document.getElementById("userName").value; function handleSuccess(o){   var userName= trim(o.responseText);  document.write(userName);    }function handleFailure(){alert("系统错误，请稍后再试！");return; }var getNameCallback = {   success: handleSuccess,   failure: handleFailure,  cache:false};var url = "{调用地址}"; var userName= "userName="+userName;var request = YAHOO.util.Connect.asyncRequest('POST', url, getNameCallback , postData);}

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