Help to load table to a textbox when selecting in combobox with connection to anothe

[eliezer87]

Well I have a combobox connected to a database, then I want that when selecting an item I upload another table to a textbox, for example:

I have 2 table, Subject and credit, then I want that when selecting the subject, I load the credit in a textbox.

Heee tried many ways but I can not do it, thanks!

And forgive my bad English, thank you for the time given

[jmcilhinney]

Unless you have a reason not to, I would suggest that you execute a single query that joins the two database tables, so you can populate a single DataTable with all the data and then bind that to both controls. If you bind both controls then the TextBox will be populated automatically when you make the selection in the ComboBox. E.g.

myComboBox.DisplayMember = "NameOfColumnToDisplayInComboBox";
myComboBox.ValueMember = "NameOfPrimaryKeyColumn";
myComboBox.DataSource = myDataTable
;
 
myTextBox.DataBindings.Add("Text", myDataTable, "NameOfColumnToDisplayInTextBox");