连接ACCESS数据库时提示：至少一个参数没有被指定值。"}

dim CON As OleDbConnection
Public db_JICHUSHUJU As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=D:\ABC\KKK.mdb "
CON = New OleDbConnection(db_JICHUSHUJU)
CON.Open()
Dim daTmp As New OleDbDataAdapter( "SELECT * FROM BINGDONG WHERE Bingdong= " & Trim(TextBox2.Text), CON)
Dim dsTmp As New DataSet
Dim dtTmp As DataTable
daTmp.Fill(dsTmp, "BINGDONG ")
dtTmp = New DataTable
dtTmp = dsTmp.Tables( "Bingdong ")
If dtTmp.Rows.Count <> 0 Then
MessageBox.Show( "该记录已存在！ ", "系统提示 ", MessageBoxButtons.OK, MessageBoxIcon.Stop)
Else
strSave = "INSERT INTO BINGDONG(Bingdong) " & _
"VALUES( ' " & Trim(TextBox2.Text) & " ') "
MessageBox.Show(strSave)

TransSave(strSave)

'刷新DataGridView1的内容
ShowData( "select * from BINGDONG ", "Bingdong ")
End If


请问一下大家：为什么这段代码运行
在 daTmp.Fill(dsTmp, "BINGDONG ") 处
提示：
未处理 OleDbException
{ "至少一个参数没有被指定值。 "}

请问这是为什么？请高手指点～！


[解决办法]
Dim daTmp As New OleDbDataAdapter( "SELECT * FROM BINGDONG WHERE Bingdong= " & Trim(TextBox2.Text), CON)
Bingdong是string类型吗,如果是的话,应该加单引号

Dim daTmp As New OleDbDataAdapter( "SELECT * FROM BINGDONG WHERE Bingdong= ' " & Trim(TextBox2.Text) & " ' ", CON)