In Below input data Col1 Value are start with VD,RE,TE,BG want replace the Col5 Values if No replace to Yes… Small Amount data i have showing you… i have more 24 columns in datatable.
Well, in that case, you can utilise the following query:
yourDt.AsEnumerable.ToList.ForEach(Sub(row)
row("Col5") = if(row("Col1").ToString.Contains("VD") OR row("Col1").ToString.Contains("RE"),"Yes",row("Col5").ToString)
End Sub)