Try
                Dim col As String = Me.ComboBox2.Text
                Dim dc As DataColumn = Me.Adr2006DataSet.Tab1.Columns(col)
                Dim t As System.Type = dc.DataType
                Dim selExpr As String
 
                Select Case True
                    Case t Is GetType(System.DateTime)
                        Dim d As DateTime = CDate(Me.TextBox12.Text)
                        selExpr = " = #" & d.ToString("MM/dd/yyyy") & "#"
                        'Rowfilter setzen
                        Me.Tab1BindingSource.Filter = col & selExpr
 
                    Case t Is GetType(System.String)
                        selExpr = " LIKE '" & Me.TextBox12.Text & "*'"
                        'Rowfilter setzen
                        Me.Tab1BindingSource.Filter = col & selExpr
                End Select

VB@rchiv its the Best