WinJS.xhr() just working first time

Question

Hello everyone,

inside a file called xml.js, I have one function linked to a button.

 exportDocumentImage: function () {
var xmlDocument = new Windows.Data.Xml.Dom.XmlDocument();
...
 xmlDocument.saveToFileAsync(filedata).done(function () {
          
            createFile().done(
                        function success(result) {
                        var date = new Date();
                        WinJS.log(date + " Finish ");
                        
                        }, function error(result) {
                            WINJS.log(" error " + error.responseText);
                        }); 
                });
}

 function createFile() {

        var date = new Date();
        return WinJS.xhr({
            url: "http://example.com",
            type: "GET",
        }).then(
            function succes(result) {
                // Obtain the date that will be formatted. 
                var date = new Date();

                WinJS.log(date + "File created. Response Text " + result.responseText + "  Status " + result.status + " " + result.statusText);
                
            },
            function error(result) {
                WinJS.log("Error  creatingFile " + result.responseText);

                
            }
        );

But when I run the application, the web service is called just the first time. After that, stops to work, and I need to restart the application.
What is my problem?
I'm able to see al the log files, so the application seems to run ok, but the webservice is not being called
Thanks in advanced

David

Answer 1

This usually indicates a caching problem. Use "If-Modified-Since" header in your xhr code:

    function acquireSyndication(url) {
        return WinJS.xhr({
            url: url,
            headers: { "If-Modified-Since": "Mon, 27 Mar 1972 00:00:00 GMT" }
        });
    }

Answer 2

Vote Mike, additionally a documentation for you: How to ensure that WinJS.xhr resends requests

--James

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Answer 3

Thanks everyone ,

WinJS.xhr({
            url: "http://example.com",
            headers: { "If-Modified-Since": "Mon, 27 Mar 1972 00:00:00 GMT" }
        })

actually works ...