我認爲這是我在創建報表後關閉水晶報表時顯示的錯誤。如何解決此問題:從DBNull類型到字符串類型的轉換無效
Private Sub Populate(id As Integer, perdate As Date, controlnum As String, establishmentname As String, fname As String, mname As String, lname As String, address As String, pertype As String, ornum As String, amntpd As String, datepd As Date) Dim row As String() = New String() {id, perdate, controlnum, establishmentname, fname, mname, lname, address, pertype, ornum, amntpd, datepd} DataGridView1.Rows.Add(row) End Sub
這是
Private Sub retrieve()
DataGridView1.Rows.Clear()
sql = "SELECT * FROM tblfsesmis"
Try
Using con
con.Open()
cmd = New MySqlCommand(sql, con)
adapter = New MySqlDataAdapter(cmd)
adapter.Fill(dt)
For Each row In dt.Rows
'It's in your Populate function that you want to check the DBNull values
Populate(row(0), row(1), row(2), row(3), row(4), row(5), row(6), row(7), row(8), row(9), row(10), row(11))
Next
dt.Rows.Clear()
DataGridView1.Refresh()
End Using 'con Object will be disposed automatically
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
你能幫助我在從我的數據庫(MySQL數據庫)獲取數據到數據網格視圖代碼是如何來解決這個問題?請 !謝謝
爲什麼不將數據表設置爲datagridview的數據源? DatagridView1.DataSource = dt並刪除對dt.rows.clear的調用 –
我會在哪裏將'DatagridView1.DataSource = dt' – LecheDeCrema
我只是將數據源設置爲像Noob提到的那樣。或者另一種選擇是選擇你的列並用'ISNULL'包圍它們並用一個空字符串替換它... – Codexer