vb.net (Date Problem)

Fly_Fish

Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
        If (objcon.con_master.State = ConnectionState.Closed)
Then objcon.con_master.Open()
        Dim cmd As New OleDbCommand("insert into m_test (aa,date) values ('erer',#" & IIf(IsDate(TextBox1.Text), TextBox1.Text, DBNull.Value) & "#)", objcon.con_master)
        cmd.ExecuteNonQuery()
    End Sub


我要pass NULL value进DATE  field, by access database.
but got error message
"Syntax error in date in query expression '##'."
请问要如何pass NULL into date field??
thanks all

hokzilla

改成这样吧：

Dim cmd As New OleDbCommand("insert into m_test (aa,date) values ('erer'," & IIf(IsDate(TextBox1.Text), "#" & TextBox1.Text & "#", DBNull.Value))",

不过最好还是用parameterized query。要注意日期的格式，这样子很容易引来error。

Fly_Fish

my code:
Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click
        If (objcon.con_master.State = ConnectionState.Closed) Then objcon.con_master.Open()
        Dim cmd As New OleDbCommand("insert into m_test (aa,dd) values ('erer'," & IIf(IsDate(TextBox1.Text), "#" & TextBox1.Text & "#", DBNull.Value), objcon.con_master)
        cmd.ExecuteNonQuery()
    End Sub

but still error:
"Syntax error in INSERT INTO statement."

Fly_Fish

problem solve...........
thanks