Newbie C# - DataSet AddRow (Solved)

Question

Hello. Fairly new to C# and the DataSet concept.
I have a DataSet MediaDataSet1 that has one table MediaList with 3 columns.
I also have a form that has 3 textboxes and 2 buttons. One button to add the data input from the text boxes. One to output the data in the DataSet to XML. However the output never contains the data. I am not sure what is wrong. Below is the code in it's current state. Any help would be appreciated.

private void button1_Click(object sender, EventArgs e)
        {
            MediaDataSet1 mDS = new MediaDataSet1();
            //DataTable mDT = mDS.Tables["MediaList"];
            DataRow mDR = mDS.Tables["MediaList"].NewRow();
            mDR["MediaName"] = MediaNameTB.Text;
            mDR["MediaType"] = MediaTypeTB.Text;
            mDR["MediaLength"] = MediaLengthTB.Text;
            mDS.Tables["MediaList"].Rows.Add(mDR);
            //mDT.Rows.Add(mDR);
            //mDS.AcceptChanges();
        }

        private void button2_Click(object sender, EventArgs e)
        {
            MediaDataSet1 mDS = new MediaDataSet1();
            mDS.WriteXml("C:\\Documents and Settings\\user003\\My Documents\\testOut.xml");
        }

The XML output always only contains this.

<?xml version="1.0" standalone="yes"?>
<MediaDataSet1 xmlns="http://tempuri.org/MediaDataSet1.xsd" />

Many Thanks.
Jeremy

Jeremy Fourman · Answer

OK yes that should have been obvious to me. So how would I load a dataset and not create a new dataset every time when the Add button is clicked. I see the Load function is available to the mDS object now but I am not sure if thats what I want. Edit: Right now I am loading XML and rewriting with new entries to load on next media addition this seems to be a heavy sort of action what would be a better way? Thank you . Jeremy

Bechir Bejaoui · Answer

private void button1_Click(object sender EventArgs e) { MediaDataSet1 mDS = new MediaDataSet1(); //DataTable mDT = mDS.Tables[MediaList]; DataRow mDR = mDS.Tables[MediaList].NewRow(); mDR[MediaName] = MediaNameTB.Text; mDR[MediaType] = MediaTypeTB.Text; mDR[MediaLength] = MediaLengthTB.Text; mDS.Tables[MediaList].Rows.Add(mDR); //mDT.Rows.Add(mDR); //mDS.AcceptChanges(); } private void button2_Click(object sender EventArgs e) { OK my freind the problem is here I mean the line bellow when you use MediaDataSet1 mDS = new MediaDataSet1(); That means that you define a new blanc dataset and you load it mDS.WriteXml(C:\Documents and Settings\user003\My Documents\testOut.xml); } The XML output always only contains this. to avoid such trouble try this instead: MediaDataSet1 mDS; private void button1_Click(object sender EventArgs e) { mDS = new MediaDataSet1(); //DataTable mDT = mDS.Tables[MediaList]; DataRow mDR = mDS.Tables[MediaList].NewRow(); mDR[MediaName] = MediaNameTB.Text; mDR[MediaType] = MediaTypeTB.Text; mDR[MediaLength] = MediaLengthTB.Text; mDS.Tables[MediaList].Rows.Add(mDR); //mDT.Rows.Add(mDR); //mDS.AcceptChanges(); } private void button2_Click(object sender EventArgs e) { mDS.WriteXml(C:\Documents and Settings\user003\My Documents\testOut.xml); }