VB.NET 中的标准表达式 MS Access 更新数据类型不匹配时出错

Question

我在datagridview中删除时出错

'If I change the code as below then successfully delete in DataGridView and database
 
'If I don't hide the "ID" column

   'DataGridView1.Columns(0).Visible = False

'index column id appears that is starting at (0)


Dim iRow As Long = DataGridView1.Item(0,DataGridView1.CurrentRow.Index).Value

'In the SQL query where clause becomes id

Dim query = " DELETE FROM tblemployee WHERE ID = " & iRow

我想隐藏

Id

列（自动编号），我想用

EMPID

的 where 子句删除它。这个

EMPID

列被定义为数据类型

text

并且它是主键。也许我的代码有问题。

 Public Sub Load_Data()
        Try
            Dim dt As New DataTable()
            Dim query = "Select * From tblemployee"
            Using adapter As New OleDbDataAdapter(query, Con)
                adapter.Fill(dt)
            End Using
            Me.DataGridView1.DataSource = dt
            DataGridView1.Columns(0).Visible = False
        Catch ex As OleDbException
            MessageBox.Show(ex.Message.ToString(), "ERROR Loading")
        Finally
            Con.Close()
        End Try
    End Sub
    Private Sub DoSQL(ByVal Sql As String)
        Cmd = New OleDb.OleDbCommand
        If Con.State = ConnectionState.Closed Then Con.Open()
        Try
            Cmd.Connection = Con
            Cmd.CommandType = CommandType.Text
            Cmd.CommandText = Sql
            Cmd.ExecuteNonQuery()
            MessageBox.Show("Records Updated Completed.", "Update Status", MessageBoxButtons.OK, MessageBoxIcon.Information)
            Cmd.Dispose()
        Catch ex As Exception
            MsgBox("Error Update: " & ex.Message)
        End Try
    End Sub
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        If DataGridView1.RowCount = 0 Then Exit Sub
        Dim iRow As String = DataGridView1.Item(1, DataGridView1.CurrentRow.Index).Value
        Dim FName As String = DataGridView1.Item(2, DataGridView1.CurrentRow.Index).Value
        Dim Result As Byte = MessageBox.Show("Are you sure you want to delete the data?" & vbCrLf & "Full Name: " & FName, "Confirm Deletion", MessageBoxButtons.YesNo, MessageBoxIcon.Question, MessageBoxDefaultButton.Button2)
        If Result = DialogResult.Yes Then
            Dim query = " DELETE FROM tblemployee WHERE EMPID = " & iRow
            DoSQL(query)
            DataGridView1.Rows.Remove(DataGridView1.CurrentRow)
            Call Load_Data()
        End If
    End Sub

Answer 1

文本值应该用

' '

单引号括起来。

因此：

"DELETE FROM tblemployee WHERE EMPID = '" & iRow & "'"