Windows Forms

13-Jun-08 5:21

Hi
DataSet with 14 columns. (Only 1 row).

Form with 14 textboxes.

While initialising, each textbox is bound to the dataset:
txtWhatever.Databindings.Add("Text", dsValues, "TableName.ColumnName");

Each textbox displays the values from the dataset.

Changing the values in a textbox does not change the dataset. According to all documentation, it should.

Why won't it work with me?

I don't want to display the data in a single-row datagridview,
because it doesn't really make sense to the user.

Otherwise, I'll have to use no databinding, and on form load populate each textbox, and update the dataset on loss of focus for each textbox.

Thanks,
Nigel

darkelv13-Jun-08 5:58

13-Jun-08 5:58

Did the value get set back into the value in the dataset after focus left the textbox?

Have you tried with DataSourceUpdateMode set to OnPropertyChanged?

Nigel Mackay13-Jun-08 6:11

13-Jun-08 6:11

The dataset has no changes no matter what I try.

And yes, I have tried:
txtName.DataBindings.Add("Text",ds, "UserList.Name",true,DataSourceUpdateMode.OnPropertyChanged);

Made no difference.

I have also tried using a binding source, with breakpoints in the parse and format methods, and both get called, but the dataset remains unchanged.

While experimening, I found that a different dataset that does get updated if I use a datagridview does not get updated if I use a textbox.

darkelv16-Jun-08 1:41

16-Jun-08 1:41

Not sure if it's already solved for you, maybe check if the fields are readonly??

Nigel Mackay16-Jun-08 4:46

16-Jun-08 4:46

No, the fields are not read-only.

Because this problem is/was holding my project up, I have resorted to populating the textboxes one-by-one from the dataset, doing validating on the textboxes one-by-one, and then writing the values back to the dataset.

This does set HasChanges to true, and the changes are saved back to the database.

So I can use the table, but not an elegant way to handle things. Especially as the deal includes the source-code.

Maybe a SharpDevelop bug? Searching this forum and MSDN doesn't show anyone else with the problem, but then I imagine not many people use simple-binding to a dataset - mostly I see it where they use textboxes to change values in a gridview. I can get that to work, but then I'd have to use an invisible gridview, which is not really a better solution!!!

Nigel

darkelv16-Jun-08 5:22

16-Jun-08 5:22

You can try wrapping the datarow's column with a class with getter and setter. Remember the implement INotifyPropertyChange on the setter.

Maybe I'll try that tomorrow. Poke tongue | ;-P

Nigel Mackay17-Jun-08 4:18

17-Jun-08 4:18

With 22 columns!!!

darkelv16-Jun-08 19:57

16-Jun-08 19:57

Well, sorry to tell, the databinding works on dataset, at least on mine. The message box will display the changed value:

private void button1_Click(object sender, EventArgs e)
{
    string s = "user id=sa;password=PASSWORD;initial catalog=DATABASENAME;data source=SERVERNAME;timeout=90";
    IDbConnection con = new System.Data.SqlClient.SqlConnection(s);
    IDbCommand cmd = con.CreateCommand();
    dataSet = new DataSet();
    IDbDataAdapter adapter = new System.Data.SqlClient.SqlDataAdapter();

    cmd.CommandText = "Select * from Customers";
    adapter.SelectCommand = cmd;
    adapter.Fill(dataSet);

    if (dataSet.Tables[0].Rows.Count > 0)
    {
        this.textBox1.DataBindings.Add("Text", dataSet, "Table.CompanyName", false, DataSourceUpdateMode.OnPropertyChanged, string.Empty);
        propertyGrid1.SelectedObject = dataSet.Tables[0].Rows[0];
    }
}

private void button2_Click(object sender, EventArgs e)
{
    MessageBox.Show(dataSet.Tables[0].Rows[0]["CompanyName"].ToString());
}

Nigel Mackay17-Jun-08 4:22

17-Jun-08 4:22

Tried exactly the same bindings settings, but will just not work.

darkelv17-Jun-08 5:20