XMLHttpRequest - using POST to rewrite XML file

Question

4.50/5 (2 votes)

See more:

I managed to learn and understand how xmlhttp.open works for GET parameter, however I cant manage to make POST parameter works.

I have a text section (reading from XML file) on a webpage, and I have a input field below and a button.

I want when I press that button the text section changes to what I wrote on input field. (the xml is rewritten and read again). I'm having problems what the rewrite of the file.

XML

<div id="myDiv"><h2>Here is the content read from XML File</h2></div>
   <input type='text' id='texto' /><br />
   <input type='button' onclick='alterar()' value='testar aqui' />

C#

function alterar() {
            var xmlhttp;
            var texto = document.getElementById('texto');
            alert(texto.value);

            if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari
                xmlhttp = new XMLHttpRequest();
            }
            else {// code for IE6, IE5
                xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
            }
            xmlhttp.onreadystatechange = function () {

                if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
                    texto = xmlhttp.responseText;
                    alert("success");
                }

                else {
                   // alert("reach here");
                    alert(xmlhttp.readyState + " " + xmlhttp.status);
                }

            }

var data = "file=info.txt"  "&content=" + texto.value;
            xmlhttp.open("POST", "other.aspx", true);
            xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
            xmlhttp.send(data);

How should I process the information to xml on other.aspx in order o update the xml file ?

Can you please correct me ?

Posted 27-Feb-11 11:12am

Maxdd 7

Updated 27-Feb-11 18:00pm

Peace ON

v7

Add a Solution

Comments

Albin Abel 27-Feb-11 23:08pm

My dear, there is no word in english like 'readed' or writed :) . You havn't explained the question fully. What you are entering in the text box. The text section name in the xml?. Then what you want to write in the XML?. Please make it clear.

[no name] 28-Feb-11 0:01am

Edited for correcting spelling of rewriten and readed....

Maxdd 7 28-Feb-11 6:20am

Thanks for the correction :)

2 solutions

Solution 1

Please, Check "Content-Type". I think it should be "text/plain" since it is a txt file. but I have not tested.

Posted 27-Feb-11 11:58am

cx_jin

Comments

Maxdd 7 27-Feb-11 18:25pm

Okay, but how should I process the data to write to XML ?

Maxdd 7 27-Feb-11 21:57pm

I placed:

var content = "xpto";
var url = "info.xml";
var data = "file=" + url + "&content=" + content;
// var data = "dados";
xmlhttp.open("POST", "test.aspx", true);
//xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
xmlhttp.setRequestHeader("Content-Type", "text/plain");
xmlhttp.send(data);

and then on test.aspx.cs page load

string xpto = Page.Request.QueryString["texto"];

// Create a new file in C:\\ dir
XmlTextWriter textWriter = new XmlTextWriter("d:\\myXmFile.xml", null);
// Opens the document
textWriter.WriteStartDocument();
// Write comments
textWriter.WriteComment(xpto);

....

However still cant write what I input to XML :(

Member 10684892 30-Jan-15 7:44am

nnfngnfgnfn

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Albin Abel · Accepted Answer · 2011-02-27T18:22:00

Hi A few things wrong in your code.

1) xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");this is no problem, no need to change

2) When you are posting directly get it from the Request object, not from query string
string xpto = Page.Request.QueryString["texto"]; ..this is wrong. According to your code in the other.aspx it should be string xpto=Request["content"];

once you written to the xml then read it and use response.write(the xml content). So what you have written here will be collected through the response text.

3)this assignment texto = xmlhttp.responseText; is wrong. It should be texto.value = xmlhttp.responseText; .

So here is the corrected version of your code except the xml write and read part..

In the aspx..

XML

<asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent">
<script type="text/javascript">
    function alterar() {
        var texto = document.getElementById('texto');
        alert(texto.value);
        var xmlhttp;
        if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari
            xmlhttp = new XMLHttpRequest();
        }
        else {// code for IE6, IE5
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        }
        xmlhttp.onreadystatechange = function () {
            if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
                texto.value = xmlhttp.responseText;
                alert("success");
            }
            else {
                // alert("reach here");
                alert(xmlhttp.readyState + " " + xmlhttp.status);
            }
        }
        var data = "file=info.txt&content=" + texto.value;
        xmlhttp.open("POST", "Default2.aspx", true);
        xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
        xmlhttp.send(data);

    }
</script>
</asp:Content>
<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">
   <div id="myDiv"><h2>Here is the content readed from XML File</h2></div>
   <input type='text' id='texto' /><br />
   <input type='button' onclick='alterar()' value='testar aqui' />
</asp:Content>

in the Default2.aspx code behind in my example ..

C#

protected void Page_Load(object sender, EventArgs e)
{
    string content = Request["content"];
    Response.Write("data received " + content);
}

By pressing button you can see the response received from the default2.aspx. I think you can handle the xml reading and writing part. If any questions post comment here.