sqlconn.datac()
Dim sql As String = "select * from webadmin where id='" + Request("id") + "'"
Dim cmd As SqlCommand = New SqlCommand(sql, sqlconn.conn)
Dim rs As SqlDataReader
rs = cmd.ExecuteReader
If rs.Read Then
username.Text = rs.Item("username")
selladdress.Value = rs.Item("selladdress")
usertype.Items.FindByText(rs.Item("usertype")).Selected = True
worknum.Value = rs.Item("worknum")
manager.Value = rs.Item("manager")
If Not IsDBNull(rs.Item("code")) Then
code.Value = rs.Item("code")
'city.Items.FindByText(rs.Item("city")).Selected = True
End If
End If
cmd.Cancel()
sqlconn.conn.Close()执行到usertype.Items.FindByText(rs.Item("usertype")).Selected = True就出错,提示“未将对象引用设置到对象的实例。”,这是怎么回事,要怎么解决,各位大侠帮帮忙!
Dim sql As String = "select * from webadmin where id='" + Request("id") + "'"
Dim cmd As SqlCommand = New SqlCommand(sql, sqlconn.conn)
Dim rs As SqlDataReader
rs = cmd.ExecuteReader
If rs.Read Then
username.Text = rs.Item("username")
selladdress.Value = rs.Item("selladdress")
usertype.Items.FindByText(rs.Item("usertype")).Selected = True
worknum.Value = rs.Item("worknum")
manager.Value = rs.Item("manager")
If Not IsDBNull(rs.Item("code")) Then
code.Value = rs.Item("code")
'city.Items.FindByText(rs.Item("city")).Selected = True
End If
End If
cmd.Cancel()
sqlconn.conn.Close()执行到usertype.Items.FindByText(rs.Item("usertype")).Selected = True就出错,提示“未将对象引用设置到对象的实例。”,这是怎么回事,要怎么解决,各位大侠帮帮忙!
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" > <html>
<head>
<title>WebForm</title>
<meta name="CODE_LANGUAGE" content="Visual Basic .NET 7.1">
<meta name=vs_defaultClientScript content="JavaScript">
<meta name=vs_targetSchema content="http://schemas.microsoft.com/intellisense/ie5">
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<script runat="server" language="vb">
Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
End Sub Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init End SubSub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
dim li as ListItem = nothing
li = usertype.Items.FindByText("用户类型")
if not li is nothing then
usertype.SelectedIndex = usertype.Items.IndexOf(li)
end if
End Sub
</script>
</head>
<body>
<form id="Form1" method="post" runat="server">
<asp:DropDownList id="usertype" runat="server">
<asp:ListItem Selected="True" Value="请选择...">请选择...</asp:ListItem>
<asp:ListItem Value="用户类型">用户类型</asp:ListItem>
</asp:DropDownList>
<asp:Button id="Button1" runat="server" Text="Button" onclick="Button1_Click"/>
</form>
</body>
</html>
li = usertype.Items.FindByText("用户类型")
if not li is nothing then
usertype.SelectedIndex = usertype.Items.IndexOf(li)
end if
为什么li总是空呀?
用参数