vb.net 和 mysql '未知列（*'我制作的列 idb 中选定行的第一个字母'*）在 where 子句中

Question

i'm trying to delete the selected row, but when i click the button delete it gives me a warning

'unknown column 'c' in where clause.

actually not only that rows ,but each rows that selected ''unknown column ( 'firstletter of selected row in column idb that i made' ) in where clause.

here are my codes.

for public class

Public Class DAFTAR_BUKU
    Dim Koneksi As New MySqlConnection
    Dim da As MySqlDataAdapter
    Dim ds As New DataSet
    Dim dt As New DataTable
    Dim command As MySqlCommand
    Dim id_cell As Char
    Dim i As Integer
    Dim query As String

for function delete

 Private Sub delete(kdbk As Char)

        Dim query As String = "delete from daftarbuku where idb= " & kdbk
        command = New MySqlCommand(query, Koneksi)

        Try
            Koneksi.Open()
            da.DeleteCommand = Koneksi.CreateCommand()
            da.DeleteCommand.CommandText = query

            If MessageBox.Show("sure", "delete", MessageBoxButtons.OKCancel, MessageBoxIcon.Warning) = Windows.Forms.DialogResult.OK Then

                If command.ExecuteNonQuery() > 0 Then
                    MsgBox("DELETED")
                    cleartext()
                End If
            End If
            Koneksi.Close()
            DataGridView1.Rows.RemoveAt(i)
        Catch ex As Exception

            MsgBox(ex.Message)

        End Try

    End Sub

for button delete

Private Sub del_Click(sender As Object, e As EventArgs) Handles del.Click
        delete(id_cell)
        GRID()
End Sub

Answer 1

Based on your code, I am assuming that the column idb is integer. Therefore you are passing integer into your function which accept char .

You can either change char to integer or change id_cell to id_cell.tostring .

Also in your catch exception since you are using mysql, use ex as MySqlException and in MessageBox, MsgBox(ex.toString) .

You can understand better from the detailed exception error shown next time.