在VB.Net中動態更新SQL Server數據庫

Question

我試圖動態地使用我的預訂表單中的文本框值來生成一個查詢，以僅更新用戶輸入的那些值。

我使用下面的代碼：

Dim str As String 

str = "UPDATE Bookings SET " 
Dim first As Integer = 1 
For Each x As Control In Me.Controls 
    If x.GetType Is GetType(TextBox) Then 
     If first = 1 Then 
      first = 2 
     Else 
      str &= "," 
     End If 
     If x.Tag = 1 Then 
      str = str & x.Name & " = @" & x.Name 
     End If 
    End If 
Next 

但它產生這樣的查詢：

Update Bookings SET ,,booking_date = @booking_date,,,,,cust_name = @cust_name where bookingID = @bookingID 

或者，如果我想更新僅有1場它生成此：

Update Bookings SET ,,,,,,,cust_name = @cust_name where bookingID = @bookingID 

Answer 1

Dim str As String 
str = "UPDATE Bookings SET " 
Dim comma As string = "" 
For Each x As Control In Me.Controls 
    If x.GetType Is GetType(TextBox) Then 
    If x.Tag = 1 Then 
     str &= comma & x.Name & " = @" & x.Name 
     comma = "," 
    End If 
    End If 
Next 

這裏是th e一行答案。

Dim str = "UPDATE Bookings SET " & String.Join(",", (From _E In Controls.OfType(Of Control)() Where _E.GetType() Is GetType(TextBox) AndAlso _E.Tag = "1" Select _E.Name).ToList())