There is no setting to always display the list and disallow entering a new value.

vb net combo box validating-32

For an example of how to use this feature, see the List Control class.

The first field in my datagridview is a combobox and the field does not allow nulls. What I want is if they don't choose a value and go to leave the field I want it to e.

If the string collections are not empty, they become read-only when you derive another form..

The ability to store values that are different from displayed text is inherited from List Control.

The list then displays the default string value for each object.

You can add individual objects with the Add method.

I have created a data input form that updates a table.

On my input form I have a combo box that updates a field that does not allow nulls.

There are several third-party (Dev Express, for example) packages that provide Combo Boxes that allow you to inspect both the initial and the new values when the value changes and cancel the change if desired, but the Combo Box provided in System. While the package can be pricey, the controls themselves are very high-quality.