Get XML with HttpWebRequest and display results

Question

Guys I think I'm somewhere near with the below but also way off the mark still, I'm trying to fetch an xml then display the results into a datagrid using the below Webrequest, it doesn't throw an error but then It doesn't display either, am I missing the xml read part or am I overlooking something simple?

HttpWebRequest request = WebRequest.Create(http://myurl/xml) as HttpWebRequest;


                // Get response
                using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
                {

                     // Load data into a dataset


                    DataSet dsWeather = new DataSet();
                    dsWeather.ReadXml(response.GetResponseStream());



                    // display dataset information
                    dataGridView1.DataSource = dsWeather;

}

Sam Hobbs · Answer

It is not a matter of being offended, it is a matter of time. You were not benefiting from what I said and explicitly asked for help from just Vulpes.

Vulpes · Answer

In response to your question on databinding, you can certainly bind to textboxes rather than a DGV. Remember though that (unless you do some prior processing) the textboxes are only going to be able to show a single field from a single row of a datatable. Depending on the nature of the XML file, they make not therefore be a suitable display vehicle.

mike Delvotti · Answer

Sam, it's not like that – I'm not ignoring your help I'm grateful of everybody's reply. I appreciate your help and I'm sorry if I've offended you.

Sam Hobbs · Answer

Note that Vulpes just suggested that you blindly try the first table. My suggestion was to look at the tables that were available. Since you are asking for help from just Vulpes and ignoring my help, I will stop trying to help.

mike Delvotti · Answer

Ahh - I got it working, Sam, yes you are right I did use the code from one of those sites as an example, but Vulpes that tip helped with the dataGridView1.DataSource = dsWeather.Tables[0];, as it then threw an error which pointed me in the right direction (I had my url wrong ;) Just one other quick question vulpes, now it works binding to a datagrid could I dislpay the results to say textbox1, textbox2 and so on instead of a datagrid? Thanks guys.

Sam Hobbs · Answer

This thread inspired me to try something I have been wanting to try. It took more analyses than we would like it to, but I managed to fetch a "Now Playing" list from our Tivo. If you don't know what that is then ignore that, but this code can certainly retrieve XML files from other systems. I said "ReadXml returns a DataSet, not a table". For example see How To Read XML Data into a DataSet by Using Visual C# .NET ; it shows use of the DataMember to specify a table name. You probably copied sample code from one of the following two sites. If not then perhaps you are missing some useful code. Using Returned XML with C# - Yahoo! Developer Network Sommers tech journal: Using Returned XML with C# That sample code is a console program that shows the tables in the data set created when a XML file is read. You can use that sample code to test the part of your code that gets the XML file.

Vulpes · Answer

It must therefore be a problem with the databinding. As Sam intimated earlier, I'd try binding to the first DataTable rather than the DataSet as a whole: dataGridView1.DataSource = dsWeather.Tables[0];

mike Delvotti · Answer

hi vulpes, no i'm trying this from a button click just to test. i've also put it in a try/catch event but no errors are thrown. the xml i'm contacting sits on a web server, i send the url with my credentials then bring back the xml, i'm fairly sure it gets to the xml it just won't fetch it back and read it into my datagridview?

Vulpes · Answer

Mike, are you doing this in the Form_Load eventhandler by any chance? If you are, then I'd place it in a try/catch block to see whether an exception is in fact being thrown. As Sam, Suthish & I discovered in another recent thread, uncaught exceptions thrown in Form_Load are ignored by the debugger which instead immediately displays the form. Alternatively, try running it in release rather than debug mode and see whether an exception is thrown then.

mike Delvotti · Answer

it doesn't return anything the datagridview just simply doesn't fill. but i'm sure it's contacting the xml.

Sam Hobbs · Answer

First note that usuallly a BindingSource is used to bind data to a control. Second note that ReadXml returns a DataSet, not a table. You need to specify which table in the data set to use. The sample that you copied probably shows that. It shows the data that was read, correct? Try using the sample as-is to see what tables are returned.

mike Delvotti · Answer

It returns data, but I have to specify what fields to bring back, the fields to collect should be like so: It doesn't populate the datagrid with any info but I'm sure it's contacting the remote xml file.

Suthish Nair · Answer

Code seems to be ok.. Did the url returns required output? Put a break point on dsWeather and check it returns data table with records. Did your DataGridview have same structure as data table?

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