mxXmlRequest

XML HTTP request wrapper. See also: mxUtils.get, mxUtils.post and mxUtils.load. This class provides a cross-browser abstraction for Ajax requests.

Encoding

For encoding parameter values, the built-in encodeURIComponent JavaScript method must be used. For automatic encoding of post data in mxEditor the mxEditor.escapePostData switch can be set to true (default). The encoding will be carried out using the conte type of the page. That is, the page containting the editor should contain a meta tag in the header, eg. <meta http-equiv=”Content-Type” content=”text/html; charset=UTF-8”>

Example

var onload = function(req)
{
  mxUtils.alert(req.getDocumentElement());
}

var onerror = function(req)
{
  mxUtils.alert('Error');
}
new mxXmlRequest(url, 'key=value').send(onload, onerror);

Sends an asynchronous POST request to the specified URL.

Example

var req = new mxXmlRequest(url, 'key=value', 'POST', false);
req.send();
mxUtils.alert(req.getDocumentElement());

Sends a synchronous POST request to the specified URL.

Example

var encoder = new mxCodec();
var result = encoder.encode(graph.getModel());
var xml = encodeURIComponent(mxUtils.getXml(result));
new mxXmlRequest(url, 'xml='+xml).send();

Sends an encoded graph model to the specified URL using xml as the parameter name. The parameter can then be retrieved in C# as follows:

string xml = HttpUtility.UrlDecode(context.Request.Params["xml"]);

Or in Java as follows

String xml = URLDecoder.decode(request.getParameter("xml"), "UTF-8").replace("\n", "&#xa;");

Note that the linefeeds should only be replaced if the XML is processed in Java, for example when creating an image.

Summary

mxXmlRequest	XML HTTP request wrapper.
Functions
mxXmlRequest	Constructs an XML HTTP request.
Variables
url	Holds the target URL of the request.
params	Holds the form encoded data for the POST request.
method	Specifies the request method.
async	Boolean indicating if the request is asynchronous.
binary	Boolean indicating if the request is binary.
withCredentials	Specifies if withCredentials should be used in HTML5-compliant browsers.
username	Specifies the username to be used for authentication.
password	Specifies the password to be used for authentication.
request	Holds the inner, browser-specific request object.
decodeSimulateValues	Specifies if request values should be decoded as URIs before setting the textarea value in simulate.
Functions
isBinary	Returns binary.
setBinary	Sets binary.
getText	Returns the response as a string.
isReady	Returns true if the response is ready.
getDocumentElement	Returns the document element of the response XML document.
getXml	Returns the response as an XML document.
getStatus	Returns the status as a number, eg.
create	Creates and returns the inner request object.
send	Send the request to the target URL using the specified functions to process the response asychronously.
setRequestHeaders	Sets the headers for the given request and parameters.
simulate	Creates and posts a request to the given target URL using a dynamically created form inside the given document.

Functions

mxXmlRequest

function mxXmlRequest( url,
params,
method,
async,
username,
password )

Constructs an XML HTTP request.

Parameters

url	Target URL of the request.
params	Form encoded parameters to send with a POST request.
method	String that specifies the request method. Possible values are POST and GET. Default is POST.
async	Boolean specifying if an asynchronous request should be used. Default is true.
username	String specifying the username to be used for the request.
password	String specifying the password to be used for the request.

Variables

url

mxXmlRequest.prototype.url

Holds the target URL of the request.

params

mxXmlRequest.prototype.params

Holds the form encoded data for the POST request.

method

mxXmlRequest.prototype.method

Specifies the request method. Possible values are POST and GET. Default is POST.

async

mxXmlRequest.prototype.async

Boolean indicating if the request is asynchronous.

binary

mxXmlRequest.prototype.binary

Boolean indicating if the request is binary. This option is ignored in IE. In all other browsers the requested mime type is set to text/plain; charset=x-user-defined. Default is false.

withCredentials

mxXmlRequest.prototype.withCredentials

Specifies if withCredentials should be used in HTML5-compliant browsers. Default is false.

username

mxXmlRequest.prototype.username

Specifies the username to be used for authentication.

password

mxXmlRequest.prototype.password

Specifies the password to be used for authentication.

request

mxXmlRequest.prototype.request

Holds the inner, browser-specific request object.

decodeSimulateValues

mxXmlRequest.prototype.decodeSimulateValues

Specifies if request values should be decoded as URIs before setting the textarea value in simulate. Defaults to false for backwards compatibility, to avoid another decode on the server this should be set to true.

Functions

isBinary

mxXmlRequest.prototype.isBinary = function()

Returns binary.

setBinary

mxXmlRequest.prototype.setBinary = function( value )

Sets binary.

getText

mxXmlRequest.prototype.getText = function()

Returns the response as a string.

isReady

mxXmlRequest.prototype.isReady = function()

Returns true if the response is ready.

getDocumentElement

mxXmlRequest.prototype.getDocumentElement = function()

Returns the document element of the response XML document.

getXml

mxXmlRequest.prototype.getXml = function()

Returns the response as an XML document. Use getDocumentElement to get the document element of the XML document.

getStatus

mxXmlRequest.prototype.getStatus = function()

Returns the status as a number, eg. 404 for “Not found” or 200 for “OK”. Note: The NS_ERROR_NOT_AVAILABLE for invalid responses cannot be cought.

create

mxXmlRequest.prototype.create = function()

Creates and returns the inner request object.

send

mxXmlRequest.prototype.send = function( onload,
onerror,
timeout,
ontimeout )

Send the request to the target URL using the specified functions to process the response asychronously.

Note: Due to technical limitations, onerror is currently ignored.

Parameters

onload	Function to be invoked if a successful response was received.
onerror	Function to be called on any error. Unused in this implementation, intended for overriden function.
timeout	Optional timeout in ms before calling ontimeout.
ontimeout	Optional function to execute on timeout.

setRequestHeaders

mxXmlRequest.prototype.setRequestHeaders = function( request,
params )

Sets the headers for the given request and parameters. This sets the content-type to application/x-www-form-urlencoded if any params exist.

Example

request.setRequestHeaders = function(request, params)
{
  if (params != null)
  {
    request.setRequestHeader('Content-Type',
            'multipart/form-data');
    request.setRequestHeader('Content-Length',
            params.length);
  }
};

Use the code above before calling send if you require a multipart/form-data request.

simulate

mxXmlRequest.prototype.simulate = function( doc,
target )

Creates and posts a request to the given target URL using a dynamically created form inside the given document.

Parameters

docs	Document that contains the form element.
target	Target to send the form result to.