Question

我正在尝试从数据库中填充文本框，在下拉列表中选择的索引已更改，但没有回页。

我尝试了以下代码，但它不起作用

<script runat="server">
private String queryString;

protected void Page_PreRender(object sender, EventArgs e)
{
 if (!String.IsNullOrEmpty(queryString))
    {
        Class1 obj = new Class1();
        if (ddlEmployee.SelectedIndex >= 0)
        {
            System.Data.DataSet ds = obj.BindDataSet("Select ID,Email from EmployeeDetails where ID=" + ddlEmployee.SelectedValue);
            txtEmail.Text = ds.Tables[0].Rows[0][1].ToString();
        }
    }
}

protected void Page_Init(object sender, EventArgs e)
{
    queryString = "?foo=bar;a=b";
}
</script>

Answer 1

查看ASP.NET PageMethods。这是一个示例：

<form id="form1" runat="server">
        <asp:ScriptManager ID="ScriptManager1" runat="server" EnablePageMethods="true"></asp:ScriptManager>
        <asp:DropDownList ID="ddlEmployee" runat="server">
            <asp:ListItem Selected="True" Value="1">One</asp:ListItem>
            <asp:ListItem Value="2">Two</asp:ListItem>
            <asp:ListItem Value="3">Three</asp:ListItem>
            <asp:ListItem Value="4">Four</asp:ListItem>
            <asp:ListItem Value="5">Five</asp:ListItem>
        </asp:DropDownList>
        <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</form>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>
<script type="text/javascript">
        $(function () {
                $("#ddlEmployee").on("change", function () {
                PageMethods.SetText($(this).val(), OnSetCompleted);
        });

        function OnSetCompleted(result) {
            $("#TextBox1").val(result);
        }
</script>

在代码隐藏中：

[System.Web.Services.WebMethod()]
[System.Web.Script.Services.ScriptMethod()]
public static string SetText(string id)
{
        //do your DB stuff here
        return "You selected " + id;
}

检查这些：

http://weblogs.asp.net/jalpeshpvadgama/archive/2012/01/07/asp-net-page-methods-with-parameters.aspx

http://encosia.com/using-jquery-to-directly-call-aspnet-ajax-page-methods/

dropdown selectedindexchanged没有回发而不需要updatepanel

1 个答案: