在DropDownList里绑定数据源,
如下:
当我加上'If IsDBNull(dr.Read()) = False Then时,第一条记录就显示不出来???这是什么原因啊!跟踪了半天也不知道为什么?那位高手给指点一下! Private Sub ddlMaxC_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ddlMaxC.SelectedIndexChanged
Dim getMaxC As String
getMaxC = ddlMaxC.SelectedItem.Value
Dim selStr As String = "select * from art_minCat where art_maxCatID='" & getMaxC & "'"
If scon.State = ConnectionState.Closed Then
scon.Open()
End If
Dim scom As New SqlCommand(selStr, scon) Dim dr As SqlDataReader = scom.ExecuteReader()
'If IsDBNull(dr.Read()) = False Then
With ddlMinC
.DataSource = dr
.DataTextField = "art_minCatName"
.DataValueField = "art_minCatID"
.DataBind()
End With
scom.Connection.Close()
'End If
End Sub
如下:
当我加上'If IsDBNull(dr.Read()) = False Then时,第一条记录就显示不出来???这是什么原因啊!跟踪了半天也不知道为什么?那位高手给指点一下! Private Sub ddlMaxC_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ddlMaxC.SelectedIndexChanged
Dim getMaxC As String
getMaxC = ddlMaxC.SelectedItem.Value
Dim selStr As String = "select * from art_minCat where art_maxCatID='" & getMaxC & "'"
If scon.State = ConnectionState.Closed Then
scon.Open()
End If
Dim scom As New SqlCommand(selStr, scon) Dim dr As SqlDataReader = scom.ExecuteReader()
'If IsDBNull(dr.Read()) = False Then
With ddlMinC
.DataSource = dr
.DataTextField = "art_minCatName"
.DataValueField = "art_minCatID"
.DataBind()
End With
scom.Connection.Close()
'End If
End Sub
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