Winform Combobox Databinding problem. Is this a bug or normal operation?

Question

Hi I have a question. I am using the standard winform ComboBox who's text value is databound to my bindingsource. Everything seems to work correctly however if I have the style of the combobox set to DropDownList and I change the value of the control by tabing over to it and then using the up/down arrow keys then the new value within the combobox does NOT get sent to the datasource if however I click on the control and change the value using the mouse then the change makes it to the datasource if I then change the property of the comboboxex to dropdown it seems to save the change to the datasource regardless if I tab and change the value using the up or down arrows or change it with the mouse.. Any Help would be greatly appreciated. Is this normal operation or a bug? Thanks

Rob Dob · Answer

This solution does NOT work the value is not sent to the datasource. Can you please try my code.. You can download a copy of my project from the link below: http://www.classifieds.ca/publicfiles/comboboxtest.zip if you tab between the two combo box's and us the up/down arrow keys to change the value within the combobox and then select the save button the value never propagates itself to the datasource. Thanks

Kirtan Patel · Answer

Friend Its not Bug Its Happening Because when you click button the Combo box Loose its Focus and Current Focus is Set to Button1 so its happening :) and When ComboBox is in DropDown Mode it having TextBox for editing and After Pressing Button When you Press Up Key It Focus on ComboBox Editable Text Box . If you Put One Text Box below the Combo Box And Press Button then Press down key The TextBox will also Get Focus :) its because of its Editable Nature its not a Bug :) just Modify you code like below it will work correctly :) private void button1_Click( object sender EventArgs e) { DataTableTestBindingSource.EndEdit(); MessageBox .Show((( DataRowView )DataTableTestBindingSource.Current)[ WallType ].ToString()); //Focus ComboBox Manually comboBox1.Focus(); }

Rob Dob · Answer

Hi Thank you I did not find a place within this forum to upload a projest so I've attached the code below that demonstrates the problem. Please create a c# winform project on your end and on the default form drag both a combobox and and button onto it. Next change the Style of the ComboBox to DropDownList and then use the code I have supplied you below for both the form_Load and Button1_Click methods. Now to show the bug first use your up/down arrow key to change the value of the combo box then click on your Button in your form you will notice that the value of the Datasource does NOT reflect what is in the ComboBox if you now select it using the mouse then it will work. Also if you change the Style of your combobox from DropDownList to just DropDown then it works as well. Here is the code.. private void Form1_Load( object sender EventArgs e) { comboBox1.Items.AddRange( new string [] { Solid  No Wall }); DataSet dataSetTest = new DataSet ( dataSetTest ); dataSetTest.Tables.Add( DataTable1 ); dataSetTest.Tables[ DataTable1 ].Columns.Add( WallType  typeof ( string )); dataSetTest.Tables[ DataTable1 ].Rows.Add( Solid ); DataTableTestBindingSource = new BindingSource ( dataSetTest DataTable1 ); comboBox1.DataBindings.Add( Text  DataTableTestBindingSource WallType ); } private void button1_Click( object sender EventArgs e) { DataTableTestBindingSource.EndEdit(); MessageBox .Show( (( DataRowView )DataTableTestBindingSource.Current)[ WallType ].ToString() ); }

Kirtan Patel · Answer

friend  Provide the Code So That i can figure out problem :)