[Shade0001]

كود :

For Each row As DataGridViewRow In DataGridView1.Rows
    Dim day As String = row.Cells("DayColumn").Value.ToString() 
 Select Case day
        Case "Sunday"
            row.Cells("DayColumn").Value = "الأحد"
        Case "Monday"
            row.Cells("DayColumn").Value = "الاثنين"
        Case "Tuesday"
            row.Cells("DayColumn").Value = "الثلاثاء"
        Case "Wednesday"
            row.Cells("DayColumn").Value = "الأربعاء"
        Case "Thursday"
            row.Cells("DayColumn").Value = "الخميس"
        Case "Friday"
            row.Cells("DayColumn").Value = "الجمعة"
        Case "Saturday"
            row.Cells("DayColumn").Value = "السبت"
    End Select
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