我有一个简单的ASP.NET GridView，它被数据绑定到我们数据库的视图。
选择行时，会将Request添加到Session变量和Request ID TextBox。当我逐步完成整个过程时，TextBox的TextChanged事件和PostBack事件都会对此进行验证，但之后不会在网站上显示这些值。
代码发布在.NET Pad上：http://dotnetpad.net/ViewPaste/TJp2pldPkk6poP3cVzRlHQ
注意：我也尝试在Post_Lack事件的Page_Load中注释掉所有代码，但这并没有解决我的问题。
什么可以使这项工作？
代码：
<%@ Page Language="C#" %>
<%@ Import Namespace="System" %>
<%@ import Namespace="System.Web.UI.WebControls" %>
<script runat="server">
protected void Page_Load(object sender, EventArgs e) {
if (IsPostBack) {
//int nDDL = GetInteger(Session[ddlSelector.ID]);
//if (nDDL == ddlSelector.SelectedIndex) {
// int reqID = GetInteger(Session[txtRequestID.ID]);
// if ((0 < reqID) && (reqID.ToString() != txtRequestID.Text)) {
// string strEmp = IsNumeric(Session[txtEmployee.ID]) ? GetText(Session[txtEmployee.ID]) : null;
// txtRequestID.Text = reqID.ToString();
// txtEmployee.Text = strEmp;
// if (nDDL != ddlChangeTo.SelectedIndex) {
// ddlChangeTo.SelectedIndex = nDDL;
// }
// }
//}
} else {
Session[ddlSelector.ID] = null;
Session[txtRequestID.ID] = null;
Session[txtEmployee.ID] = null;
txtRequestID.Text = null;
txtEmployee.Text = null;
txtMTF.Text = null;
btnOK.Visible = (0 < GetInteger(txtRequestID.Text));
}
}
private void ErrorMessage(string message) {
Response.Write(string.Format("<font color=\"Red\"><b>{0}</b></font>", message));
}
protected void GridViewRow_Selected(object sender, EventArgs e) {
var row = GridView1.SelectedRow;
if (row != null) {
var reqIdCell = row.Cells[1];
if (reqIdCell != null) {
int reqID = GetInteger(reqIdCell.Text);
if (0 < reqID) {
Session[ddlSelector.ID] = ddlSelector.SelectedIndex;
Session[txtRequestID.ID] = reqID;
txtRequestID.Text = reqID.ToString();
txtEmployee.Text = null;
btnOK.Visible = true;
}
}
}
}
protected void Submit_Click(object sender, EventArgs e) {
int reqID = GetInteger(Session[txtRequestID.ID]);
if (0 < reqID) {
ErrorMessage("Success!");
} else {
ErrorMessage("Unrecognised Request ID.");
txtRequestID.Focus();
}
}
protected void TextBox_TextChanged(object sender, EventArgs e) {
if (sender is TextBox) {
TextBox tbx = (TextBox)sender;
if (tbx.ID == txtRequestID.ID) {
int reqID = GetInteger(txtRequestID.Text.Trim());
int reqI2 = GetInteger(Session[txtRequestID.ID]);
if (0 < reqID) {
Session[txtRequestID.ID] = reqID;
} else {
txtRequestID.Text = null;
}
if (0 < reqI2) {
txtRequestID.Text = reqI2.ToString();
}
} else if (tbx.ID == txtEmployee.ID) {
string empNum = txtEmployee.Text.Trim();
if (IsNumeric(empNum)) {
Session[txtEmployee.ID] = empNum;
} else {
txtEmployee.Text = null;
}
}
} else if (sender is DropDownList) {
DropDownList ddl = (DropDownList)sender;
if (ddl.ID == ddlSelector.ID) {
Session[ddlSelector.ID] = ddlSelector.SelectedIndex;
Session[txtRequestID.ID] = null;
Session[txtEmployee.ID] = null;
}
}
}
protected void Tick_Tock(object sender, EventArgs e) {
GridView1.DataBind();
}
private static int GetInteger(object value) {
int result = -1;
if (HasValue(value)) {
try {
result = (int)value;
} catch {
result = -1;
}
}
if (result == -1) {
result = 0; // errors could occur if I try indexing things with negative numbers
string text = GetText(value);
if (!String.IsNullOrEmpty(text)) {
int.TryParse(text.Trim(), out result);
}
}
return result;
}
private static string GetText(object value) {
if (HasValue(value)) {
return value.ToString().Trim();
}
return null;
}
private static bool HasValue(object item) {
if ((item != null) && (item != DBNull.Value)) {
return !String.IsNullOrEmpty(item.ToString().Trim());
}
return false;
}
private static bool IsNumeric(object input) {
if (input == null) return false;
string text = input.ToString();
if (!String.IsNullOrEmpty(text.Trim())) {
foreach (char c in text.ToCharArray()) {
if (char.IsLetter(c)) return false;
}
}
return true;
}
</script>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:SqlDataSource ID="productionDataSource2" runat="server" ConnectionString="<%$ ConnectionStrings:CPWEB_PRODUCTION %>" SelectCommand="SELECT [RequestID], [Employee], [DateStamp], [Line], [PartNo], [Workorder], [Qty], [MTF], [Status] FROM [vwRequestsEx] WHERE ([Status] = @Status)"><SelectParameters>
<asp:ControlParameter ControlID="ddlSelector" Name="Status" PropertyName="SelectedValue" Type="String" />
</SelectParameters></asp:SqlDataSource>
<asp:ScriptManager ID="ScriptManager1" EnablePartialRendering="true" runat="server" />
<table style="width: 90%">
<tr>
<td>Display:<br /><asp:DropDownList ID="ddlSelector" runat="server" DataSourceID="productionStatus2" DataTextField="Description" DataValueField="Description" OnSelectedIndexChanged="TextBox_TextChanged"></asp:DropDownList>
<asp:SqlDataSource ID="productionStatus2" runat="server" ConnectionString="<%$ ConnectionStrings:CPWEB_PRODUCTION %>" SelectCommand="SELECT [ID], [Description] FROM [Status]"></asp:SqlDataSource>
</td>
<td>RequestID:<br /><asp:TextBox ID="txtRequestID" runat="server" OnTextChanged="TextBox_TextChanged" AutoCompleteType="Disabled" /></td>
<td>Employee:<br /><asp:TextBox ID="txtEmployee" runat="server" OnTextChanged="TextBox_TextChanged" AutoCompleteType="Disabled" /></td>
<td>MTF:<br /><asp:TextBox ID="txtMTF" runat="server" OnTextChanged="TextBox_TextChanged" AutoCompleteType="Disabled" /></td>
<td style="width: 110px;">Change To:<br /><asp:DropDownList ID="ddlChangeTo" runat="server" DataSourceID="productionStatus3" DataTextField="Description" DataValueField="Description"></asp:DropDownList>
<asp:SqlDataSource ID="productionStatus3" runat="server" ConnectionString="<%$ ConnectionStrings:CPWEB_PRODUCTION %>" SelectCommand="SELECT [Description] FROM [Status] WHERE ([Description] <> @Description)"><SelectParameters>
<asp:ControlParameter ControlID="ddlSelector" Name="Description" PropertyName="SelectedValue" Type="String" />
</SelectParameters></asp:SqlDataSource>
</td>
<td><br />
<asp:Button ID="btnOK" runat="server" Text="Submit" OnClick="Submit_Click" Width="75px" /></td>
</tr>
<tr>
<td class="nowrap" colspan="6">
<asp:Timer ID="Timer1" OnTick="Tick_Tock" runat="server" Interval="30000"></asp:Timer>
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" runat="server">
<Triggers><asp:AsyncPostBackTrigger ControlID="Timer1" EventName="Tick" /></Triggers>
<ContentTemplate>
<asp:GridView ID="GridView1" runat="server" AllowPaging="True" AllowSorting="True" AutoGenerateColumns="False" AutoGenerateSelectButton="True" CellPadding="1" DataSourceID="productionDataSource2" EmptyDataText="No Records to Display" Font-Size="Small" ForeColor="#333333" OnSelectedIndexChanged="GridViewRow_Selected" ShowHeaderWhenEmpty="True" HorizontalAlign="Left" RowHeaderColumn="RequestID" Width="95%">
<AlternatingRowStyle BackColor="White" ForeColor="#284775" />
<Columns>
<asp:BoundField DataField="RequestID" HeaderText="RequestID" SortExpression="RequestID" />
<asp:BoundField DataField="Employee" HeaderText="Employee" SortExpression="Employee" />
<asp:BoundField DataField="DateStamp" HeaderText="DateStamp" SortExpression="DateStamp" />
<asp:BoundField DataField="Line" HeaderText="Line" SortExpression="Line" />
<asp:BoundField DataField="PartNo" HeaderText="PartNo" SortExpression="PartNo" />
<asp:BoundField DataField="Workorder" HeaderText="Workorder" SortExpression="Workorder" />
<asp:BoundField DataField="Qty" HeaderText="Qty" SortExpression="Qty" />
<asp:BoundField DataField="MTF" HeaderText="MTF" SortExpression="MTF" />
<asp:BoundField DataField="Status" HeaderText="Status" SortExpression="Status" />
</Columns>
<EditRowStyle BackColor="#999999" />
<FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
<HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" HorizontalAlign="Left" />
<PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" />
<RowStyle BackColor="#F7F6F3" ForeColor="#333333" HorizontalAlign="Left" Wrap="False" />
<SelectedRowStyle BackColor="#E2DED6" Font-Bold="True" ForeColor="#333333" />
<SortedAscendingCellStyle BackColor="#E9E7E2"></SortedAscendingCellStyle><SortedAscendingHeaderStyle BackColor="#506C8C"></SortedAscendingHeaderStyle><SortedDescendingCellStyle BackColor="#FFFDF8"></SortedDescendingCellStyle><SortedDescendingHeaderStyle BackColor="#6F8DAE"></SortedDescendingHeaderStyle></asp:GridView></ContentTemplate></asp:UpdatePanel></td>
</tr>
</table>
</div>
</form>
</body>
</html>
答案 0 :(得分：4)
发布您遇到问题的实际部分会让您更好地回答这个问题。
你不需要所有其他部分，只需这样做
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
//code to execute here only when an action is taken by the user
//and not affected by PostBack
}
//these codes should be affected by PostBack
}
希望它有所帮助！
<强>更新
我相信您的UpdatePanel是造成问题的原因。删除UpdatePanel，看起来没问题。
顶部的原因控件没有被更新是因为它们不在UpdatePanel中，你通过UpdatePanel中的控件从代码隐藏中做出的任何更改（例如，通过“选择”链接的PostBack）将永远不会到达它们。 / p>
一种解决方案是在顶部包括那些控件，例如： UpdatePanel中的RequestID文本框。
希望这有帮助！