In order to access this site you need to enable JavaScript!

You are here: Reference > JavaScript > client-side > xml handling > properties > readyState (XMLDocument)

readyState property (XMLDocument)

Browser support:

Returns an integer value that indicates the load state of the XMLDocument object.

Use this property together with the onreadystatechange event to be notified when the state changes.

The onreadystatechange event and the readyState property is useful if the load method loads an XML document asynchronously. If you want to start processing data as soon as it becomes available, use the ondataavailable event.

Syntax:

object.readyState;

You can find the related objects in the Supported by objects section below.

This property is read-only.

Possible values:

Integer that represents the state of the object.

One of the following values:

The load method was called, but no data has been received yet.

A part of the data has been loaded, but the document object model (DOM) is not yet available.

The document object model has been built from the received data and it is available.

All data has been loaded, the operation is finished.

Default: this property has no default value.

Example HTML code 1:

This example illustrates the use of the readyState property:

Code

ajax.js

<head>
    <script type="text/javascript" src="ajax.js"></script>
    
    <script type="text/javascript">
        var xmlDoc = null;

        function LoadXML () {
            xmlDoc = CreateXMLDocumentObject ();    // defined in ajax.js
            if (!xmlDoc) {
                return;
            }

            var url = "large.xml";
            xmlDoc.async = true;

            if (xmlDoc.addEventListener) {  // Firefox, Opera, Google Chrome and Safari
                xmlDoc.addEventListener("load", OnLoadXML, false);
            }
            else {
                xmlDoc.onreadystatechange = OnStateChange;
            }

            xmlDoc.load (url);
        }

        function OnLoadXML () {
            LoadingFinished ();
        }

        function OnStateChange () {
            var output = document.getElementById ("output");
            switch (xmlDoc.readyState) {
            case 1:
                output.innerHTML += "The load method was called, but no data has been received yet.<br/>";
                break;
            case 2:
                output.innerHTML += "A part of the data has been loaded, but the document object model (DOM) is not yet available.<br/>";
                break;
            case 3:
                output.innerHTML += "The document object model has been built from the received data and it is available.<br/>";
                break;
            case 4:
                LoadingFinished ();
                break;
            };
        }

        function LoadingFinished () {
            var output = document.getElementById ("output");
            output.innerHTML += "All data has been loaded, the operation is finished:<br/>";

            var errorMsg = null;
            if (xmlDoc.parseError && xmlDoc.parseError.errorCode != 0) {
                errorMsg = "XML Parsing Error: <span style='color:red'>" + xmlDoc.parseError.reason
                          + " at line " + xmlDoc.parseError.line
                          + " at position " + xmlDoc.parseError.linepos
                          + "</span><br/>";
            }
            else {
                if (xmlDoc.documentElement) {
                    if (xmlDoc.documentElement.nodeName == "parsererror") {
                        errorMsg = "<span style='color:red'>" + xmlDoc.documentElement.childNodes[0].nodeValue + "</span><br/>";
                    }
                }
            }
            if (errorMsg) {
                output.innerHTML += errorMsg;
            }
            else {
                output.innerHTML += "<span style='color:blue'>The XML is valid.</span><br/>";
            }
        }
    </script>
</head>
<body>
    <button onclick="LoadXML ()">Analyze the loading process of an XML</button>
    <br/><br/>
    <div id="output" style="width:420px; height:200px; overflow:auto; border:1px solid #000000; background-color:#f5e4b1;"></div>
</body>


function CreateHTTPRequestObject () {
        // although IE supports the XMLHttpRequest object, but it does not work on local files.
    var forceActiveX = (window.ActiveXObject && location.protocol === "file:");
    if (window.XMLHttpRequest && !forceActiveX) {
        return new XMLHttpRequest();
    }
    else {
        try {
            return new ActiveXObject("Microsoft.XMLHTTP");
        } catch(e) {}
    }
    alert ("Your browser doesn't support XML handling!");
    return null;
}

function CreateMSXMLDocumentObject () {
    if (typeof (ActiveXObject) != "undefined") {
        var progIDs = [
                        "Msxml2.DOMDocument.6.0", 
                        "Msxml2.DOMDocument.5.0", 
                        "Msxml2.DOMDocument.4.0", 
                        "Msxml2.DOMDocument.3.0", 
                        "MSXML2.DOMDocument", 
                        "MSXML.DOMDocument"
                      ];
        for (var i = 0; i < progIDs.length; i++) {
            try { 
                return new ActiveXObject(progIDs[i]); 
            } catch(e) {};
        }
    }
    return null;
}

function CreateXMLDocumentObject (rootName) {
    if (!rootName) {
        rootName = "";
    }
    var xmlDoc = CreateMSXMLDocumentObject ();
    if (xmlDoc) {
        if (rootName) {
            var rootNode = xmlDoc.createElement (rootName);
            xmlDoc.appendChild (rootNode);
        }
    }
    else {
        if (document.implementation.createDocument) {
            xmlDoc = document.implementation.createDocument ("", rootName, null);
        }
    }
    
    return xmlDoc;
}

function ParseHTTPResponse (httpRequest) {
    var xmlDoc = httpRequest.responseXML;

            // if responseXML is not valid, try to create the XML document from the responseText property
    if (!xmlDoc || !xmlDoc.documentElement) {
        if (window.DOMParser) {
            var parser = new DOMParser();
            try {
                xmlDoc = parser.parseFromString (httpRequest.responseText, "text/xml");
            } catch (e) {
                alert ("XML parsing error");
                return null;
            };
        }
        else {
            xmlDoc = CreateMSXMLDocumentObject ();
            if (!xmlDoc) {
                return null;
            }
            xmlDoc.loadXML (httpRequest.responseText);

        }
    }

            // if there was an error while parsing the XML document
    var errorMsg = null;
    if (xmlDoc.parseError && xmlDoc.parseError.errorCode != 0) {
        errorMsg = "XML Parsing Error: " + xmlDoc.parseError.reason
                  + " at line " + xmlDoc.parseError.line
                  + " at position " + xmlDoc.parseError.linepos;
    }
    else {
        if (xmlDoc.documentElement) {
            if (xmlDoc.documentElement.nodeName == "parsererror") {
                errorMsg = xmlDoc.documentElement.childNodes[0].nodeValue;
            }
        }
    }
    if (errorMsg) {
        alert (errorMsg);
        return null;
    }

        // ok, the XML document is valid
    return xmlDoc;
}

    // returns whether the HTTP request was successful
function IsRequestSuccessful (httpRequest) {
        // IE: sometimes 1223 instead of 204
    var success = (httpRequest.status == 0 || 
        (httpRequest.status >= 200 && httpRequest.status < 300) || 
        httpRequest.status == 304 || httpRequest.status == 1223);
    
    return success;
}