アップデート
Bamarが提案したように、コードを変更しました。コールバック関数を保持するためにインスタンス変数を使用しています。ただし、問題は同じままで、呼び出しごとに同じコールバック関数が使用されmakeRequest()ます。
JavaScript で http クライアントを作成しました。同期 GET および POST 呼び出しでは問題なく動作しますが、2 つ以上のコールバック関数で非同期要求を使用すると、要求ごとに同じ関数が呼び出されます。
Service.aspx ファイルは、パラメーター名の値を中継するだけなので、要求ごとに変更する必要があります。
JavaScript コードは次のとおりです。
//-- Usage examples ----------------------------------------------
/*
//Full
client = new httpClient();
client.method("get");
client.baseUrl("Service.aspx");
client.requestData({name: "John", age: 56, location: "Kansas City"});
var response = client.makeRequest();
alert(response);
//Multiple requests
client = new httpClient();
client.baseUrl("Service.aspx");
client.requestData("?q=foo");
var data = client.makeRequest();
alert(data);
client.requestData("?q=foobar");
var data = client.makeRequest();
alert(data);
//Minimal
client = new httpClient();
client.baseUrl("Service.aspx?q=test");
client.makeRequest();
//Minimal, with deafult base URL http://localhost/
client = new httpClient();
client.requestData("?q=foobar");
client.makeRequest();
//Full, with response output contained in an object
client = new httpClient();
client.method("get");
client.baseUrl("Service.aspx");
client.requestData("?q=test");
var requestObject = client.makeRequestObject();
alert(requestObject.MimeType);
alert(requestObject.charset);
//Custom callback function to handle asychronous httprequests
myCallback = function (response) {
document.getElementById("div").innerHTML += response;
}
client = new httpClient();
client.asynchronous(true);
client.method("get");
client.baseUrl("Service.aspx");
client.callback(myCallback);
client.requestData({ name: "Peter", age: 45, location: "Kansas City" });
client.makeRequest();
*/
function httpClient() {
this.$baseUrl = "http://localhost/";
this.$method = "get";
this.$requestData = "";
this.$asynchronous = false;
this.$callbackFunction = "";
this.$invokeCallback = function (func, response) {
func(response);
}
}
httpClient.prototype.method = function (requestMethod) {
this.$method = requestMethod;
}
httpClient.prototype.baseUrl = function (requestBaseUrl) {
this.$baseUrl = requestBaseUrl;
}
$_xmlhttpConstruct = function () {
var xmlhttp;
if (window.XMLHttpRequest) {//IE7+, Firefox, Chrome, Opera, Safari
return new XMLHttpRequest();
}
else {//IE6, IE5
try { return new ActiveXObject("Msxml2.XMLHTTP.6.0"); }
catch (e) { }
try { return new ActiveXObject("Msxml2.XMLHTTP.3.0"); }
catch (e) { }
try { return new ActiveXObject("Microsoft.XMLHTTP"); }
catch (e) { }
}
}
httpClient.prototype.setRequestHeader = function (header, value) {
}
httpClient.prototype.callback = function (func) {
this.$callbackFunction = func; //Does not get set to new callback function on multiple requests
}
httpClient.prototype.asynchronous = function (boolean) {
this.$asynchronous = boolean;
}
httpClient.prototype.makeRequest = function () {
//Initializing the xmlhttp object
var xmlhttp = $_xmlhttpConstruct();
if (this.$requestData == undefined) {
xmlhttp.open(this.$method, this.$baseUrl, this.$asynchronous);
}
else {
if (this.$method == "post") {
xmlhttp.open(this.$method, this.$baseUrl, this.$asynchronous);
xmlhttp.setRequestHeader('X-Requested-With', 'XMLHttpRequest');
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlhttp.setRequestHeader("Cache-Control", "no-cache, must-revalidate"); //HTTP 1.1
//xmlhttp.setRequestHeader("Pragma", "no-cache"); //HTTP 1.0
//xmlhttp.setRequestHeader("Expires", "Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past
xmlhttp.send(this.$requestData);
invokeCallback = this.$invokeCallback;
callbackFunction = this.$callbackFunction;
if (this.$asynchronous) {
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
//Callback
invokeCallback(callbackFunction, xmlhttp.responseText);
}
}
}
else {
return xmlhttp.responseText;
}
//alert("URL: " + this.$baseUrl + "\n" + "Method: " + this.$method + "\n" + "Request data: " + this.$requestData);
}
if (this.$method == "get") {
xmlhttp.open(this.$method, this.$baseUrl + this.$requestData, this.$asynchronous);
xmlhttp.setRequestHeader('X-Requested-With', 'XMLHttpRequest');
xmlhttp.setRequestHeader("Cache-Control", "no-cache, must-revalidate"); //HTTP 1.1
//xmlhttp.setRequestHeader("Pragma", "no-cache"); //HTTP 1.0
//xmlhttp.setRequestHeader("Expires", Sat, 26 Jul 1997 05:00:00 GMT"); // Date in the past
xmlhttp.send(null);
invokeCallback = this.$invokeCallback;
callbackFunction = this.$callbackFunction;
if (this.$asynchronous) {
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
//Callback
invokeCallback(callbackFunction, xmlhttp.responseText);
}
}
}
else {
return xmlhttp.responseText;
}
//alert("URL: " + this.$baseUrl + "\n" + "Full request URL: " + this.$baseUrl + this.$requestData + "\n" + "Method: " + this.$method + "\n" + "Request data: " + this.$requestData);
}
}
}
httpClient.prototype.requestData = function (data) {
this.$requestData = "";
if (typeof (data) == "object") {
var i = 0;
for (key in data) {
if (i == 0) {
if (this.$method == "get") {
this.$requestData += "?" + key + "=" + data[key];
}
if (this.$method == "post") {
this.$requestData += key + "=" + data[key];
}
i++;
}
else {
this.$requestData += "&" + key + "=" + data[key];
}
}
}
else {
this.$requestData = data;
}
}
クライアントの使用方法は次のとおりです（非同期）：
<!DOCTYPE html>
<html>
<head>
<title></title>
<script type="text/javascript" src="httpClient.js"></script>
</head>
<body>
<form id="form1">
<div id="debug"></div>
</form>
<script type="text/javascript">
//Custom callback functions to handle asychronous httprequests
function testone(response) {
document.getElementById("debug").innerHTML += "<div style='color: green;'>" + response + "</div>";
}
function testtwo(response) {
document.getElementById("debug").innerHTML += "<div style='color: red;'>" + response + "</div>";
}
clientOne = new httpClient();
clientOne.asynchronous(true);
clientOne.method("get");
clientOne.baseUrl("Service.aspx");
clientOne.callback(testone);
clientOne.requestData({ name: "Peter", age: 45, location: "Kansas City" });
clientOne.makeRequest();
//---------------------------------------------------
clientTwo = new httpClient();
clientTwo.asynchronous(true);
clientTwo.method("get");
clientTwo.baseUrl("Service.aspx");
clientTwo.callback(testtwo);
clientTwo.requestData({ name: "Mary", age: 45, location: "Kansas City" });
clientTwo.makeRequest();
//Synchronous works!
/*
client = new httpClient();
client.asynchronous(false);
client.method("get");
client.baseUrl("Service.aspx");
client.requestData({ name: "Peter", age: 45, location: "Kansas City" });
testone(client.makeRequest());
client.requestData({ name: "Mary", age: 45, location: "Kansas City" });
testtwo(client.makeRequest());
*/
</script>
</body>
</html>