When the combobox text is "- Select a City -", the validator detects an error and displays the message "You must select a city!": When the combobox text is set to a city, the validator accepts the selection: Validates to make sure the user entered a value.By default, all validators on the web page must be successful before a postback can occur.
When no Validation Group is specified, all validators will execute when a post-back to the server is made.
The reason of this beahvior is that both the validators and the Rad Combo Box have an empty string set as a default value of the Validation Group property.
The validator controls including Rad Combo Box, have a Validation Group property.
The Rad Combo Box validation is activated only by those validators whose Validation Group property matches the Validation Group property of the Rad Combo Box.
My datagridview has a combobox column, the combobox has 2 values. When data is loaded to the datagridview the columns values are empty, number of rows doesn't matter but only 1 row can have the value "A" and only 1 row can have the value "B". Column Index = 5 Then For Each row As Data Grid View Row In dg. MSDN states: The Value property is the actual data object contained by the cell, whereas the Formatted Value is the formatted representation of this object. Column Index = 5 Then Dim Curr Value as string = dg.rows(e.