XMLHttpRequest 跨域请求webservice

function test() {

var xhr = new XMLHttpRequest();

xhr.onreadystatechange = function () {

if (xhr.readyState === 4) {

if (xhr.status === 200) {

document.write("成功");

document.write(xhr.responseText);

}

else {

document.write("失敗");

}

}

};

var url = "http://localhost:17659/WebSite5/Service.asmx/HelloWorld?msg=gong";

xhr.open("GET", url, true);

xhr.send();

}

 

 

[WebMethod]
public string HelloWorld(string msg)
{
Context.Response.AddHeader("Access-Control-Allow-Origin", "*");
Context.Response.AddHeader("Access-Control-Allow-Methods", "*");
Context.Response.AddHeader("Access-Control-Allow-Headers", "x-requested-with,content-type");

return "Hello World"+msg+"123";
}