DataGridView中的整數輸入驗證

Question

我可以使用下面的代碼來檢查用戶是否在datagridview單元格中輸入字符串。如果用戶輸入一個字符串，會彈出一條消息告訴他們「只允許數字輸入」。這正是我想要我的代碼做的。但是，如果我嘗試在填充數字的數據列中使用此代碼，我會收到一條錯誤消息，指出「發生錯誤，解析提交」。如果有人能夠找出問題在這裏，我將不勝感激！

If (e.ColumnIndex = 3) Then 'checking numeric value for column 3 only 
     Dim value As String = DataGridView1.Rows(e.RowIndex).Cells(e.ColumnIndex).Value 
     For Each c As Char In value 
      If Not Char.IsDigit(c) Then 
       MessageBox.Show("Please Enter numeric Value") 
       DataGridView1.Rows(e.RowIndex).Cells(e.ColumnIndex).Value = 3 'This will set the defaultvalue of the datagrid cell in question to the value of "3" 
       Exit Sub 
      End If 
     Next 
    End If 

Answer 1

爲此在cellvalidating事件......

If (e.ColumnIndex = 3) Then 'checking numeric value for column 3 only 

    If Not Isnumeric(e.Formatted.Value) Then 

     MessageBox.Show("Please Enter numeric Value") 
     DataGridView1.Rows(e.RowIndex).Cells(e.ColumnIndex).Value = 3 'This will set the defaultvalue of the datagrid cell in question to the value of "3" 
     Exit Sub 

    End If 

End If 

Answer 2

這種解決方案對於非整數不僅檢查重視它也適用於填充了整個datagridview的數字每列。另外，如果用戶輸入非整數，如果將爲datagridviewcell提供默認值，則此默認值爲前一個數字。

Private Sub DataGridView1_DataError(ByVal sender As Object, _ 
ByVal e As DataGridViewDataErrorEventArgs) _ 
Handles DataGridView1.DataError 

    If StrComp(e.Exception.Message, "Input string was not in a correct format.") = 0 Then 
     MessageBox.Show("Please Enter a numeric Value") 
     'This will change the number back to original 
     DataGridView1.Rows(e.RowIndex).Cells(e.ColumnIndex).Value = " " 
    End If 




End Sub