我正在使用Visual Studio 2010和Visual Basic来设计Web应用程序。
我有一个gridview，每行都有一个按钮，用于打开一个新网页，并使用点击的行按钮填充字段。工作良好。问题是 - 我希望用户能够编辑新网页上的字段 - 没有运气。改变它，它从gridview变回值。这些字段如何变得可编辑？我当时认为它可能是一个TextChanged事件，但我不能让它工作。
这是我的代码的一部分。提前谢谢！
ASPX
<%@ Page Title="" Language="vb" AutoEventWireup="true" MasterPageFile="~/Site.Master" CodeBehind="TimeOffNoRequestEdit.aspx.vb" Inherits="timework.TimeOffNoRequestEdit" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<asp:ToolkitScriptManager ID="toolkitScriptManager" runat="server" />
<asp:Label ID="Label2" runat="server"
style="color: #990033; font-weight: 700"></asp:Label>
<asp:Label ID="Label1" runat="server"
style="color: #000099; font-weight: 700"></asp:Label>
<br />
<label>Employee Name:</label><asp:TextBox ID="TextBox3" runat="server" BorderStyle="None"
style="margin-left: 0px; font-size: medium; font-weight: 700;"
Width="150px" Height="22px" AutoPostBack="True"></asp:TextBox>
<asp:TextBox ID="TextBox4" runat="server" Width="129px"
AutoPostBack="True" Visible="False"></asp:TextBox>
<br />
<hr align="left" style="width: 791px; margin-left: 0px" />
<label>Date Requested:</label><asp:TextBox ID="DateRequested" runat="server" style="margin-left: 0px; font-size: medium; font-weight: 500;"
Width="150px" Height="22px" AutoPostBack="True" BorderStyle="None"></asp:TextBox>
<br />
<p />
<label>Begin Date Off:</label><asp:TextBox ID="TextBox1" runat="server" style="margin-left: 10px; font-size: medium; font-weight: 500;"
Width="150px" Height="22px" AutoPostBack="True" BorderStyle="None"></asp:TextBox>
<br />
<label> End Date Off:</label><asp:TextBox ID="TextBox2" runat="server" style="margin-left: 15px; font-size: medium; font-weight: 500;"
Width="150px" Height="22px" AutoPostBack="True" BorderStyle="None"></asp:TextBox>
<p />
<label> All Day?</label> <asp:CheckBox ID=Checkbox1 runat="server" />
<br />
<label>Begin Time Off:</label> <asp:TextBox ID="TextBox6" runat="server" style="margin-left: 12px; font-size: medium; font-weight: 500;"
Width="150px" Height="22px" AutoPostBack="True" BorderStyle="None"></asp:TextBox>
<br />
<label> End Time Off:</label> <asp:TextBox ID="TextBox7"
runat="server" style="margin-left: 12px; font-size: medium; font-weight: 500;"
Width="148px" Height="22px" AutoPostBack="True" BorderStyle="None"></asp:TextBox>
<br />
<br />
<label> Reason:<asp:TextBox
ID="TextBox5" runat="server" style="margin-left:10px; font-size: medium; font-weight: 500;"
Width="150px" Height="22px" AutoPostBack="True" BorderStyle="None"></asp:TextBox></label>
<br />
<br />
<asp:Button ID="Button1" runat="server" Text="Save" />
</asp:Content>
Visual Basic
Private Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
Dim windowsLoginName As System.String = HttpContext.Current.User.Identity.Name 'System.Security.Principal.WindowsIdentity.GetCurrent().Name
Dim split As String() = Nothing
Dim vname As String
Dim sqlConnection As New SqlConnection("Data Source=janetdev;Initial Catalog=TimeSQL;Persist Security Info=True;User ID=sa;Password=password")
Dim cmd, cmd1, cmd2 As New SqlCommand
Dim returnValue, returnValue1, returnValue2 As Object
Dim dt As Date = Today
'Get network login name (name only)
split = windowsLoginName.Split("\".ToCharArray)
vname = split(1)
'Get firstname from tblEmployees that matches login name
cmd.CommandText = "SELECT FirstName FROM tblEmployees where login = '" & vname & "'"
cmd.CommandType = CommandType.Text
cmd.Connection = sqlConnection
'Get lastname from tblEmployees that matches login name
cmd1.CommandText = "SELECT LastName FROM tblEmployees where login = '" & vname & "'"
cmd1.CommandType = CommandType.Text
cmd1.Connection = sqlConnection
'Get employeeid from tblEmployees that matches login name
cmd2.CommandText = "SELECT EmployeeID FROM tblEmployees where login = '" & vname & "'"
cmd2.CommandType = CommandType.Text
cmd2.Connection = sqlConnection
sqlConnection.Open()
'firstname
returnValue = cmd.ExecuteScalar()
'lastname
returnValue1 = cmd1.ExecuteScalar()
'employeeid
returnValue2 = cmd2.ExecuteScalar()
sqlConnection.Close()
'display firstname and lastname on screen
TextBox3.Text = returnValue & " " & returnValue1
TextBox4.Text = returnValue2
'display today's date
DateRequested.Text = dt
'Get value of other fields
If Not [String].IsNullOrEmpty(Request.QueryString("BeginDateOff").ToString()) Then
'Retrieving the BeginDateOff Value
TextBox1.Text = Request.QueryString("BeginDateOff").ToString()
End If
If Not [String].IsNullOrEmpty(Request.QueryString("EndDateOff").ToString()) Then
'Retrieving the EndDateOff Value
TextBox2.Text = Request.QueryString("EndDateOff").ToString()
End If
If Not [String].IsNullOrEmpty(Request.QueryString("BeginTimeOff").ToString()) Then
'Retrieving the BeginTimeOff Value
TextBox6.Text = Request.QueryString("BeginTimeOff").ToString()
End If
If Not [String].IsNullOrEmpty(Request.QueryString("EndTimeOff").ToString()) Then
'Retrieving the EndTimeOff Value
TextBox7.Text = Request.QueryString("EndTimeOff").ToString()
End If
'Retrieving the All Day Value
Checkbox1.Checked = Boolean.Parse(Request.QueryString("AllDay_YesNo"))
If Not [String].IsNullOrEmpty(Request.QueryString("Description").ToString()) Then
'Retrieving the Description Value
TextBox5.Text = Request.QueryString("Description").ToString()
End If
DateRequested.Focus()
End Sub
答案 0 :(得分：1)
您需要在填充文本框之前使用if(!PostBack) - 否则您将在每次回发时使用原始值重写它们。
<强>更新
Page_Load会在每次回发，自动（AutoPostBack）或手动（按钮点击）上运行，并且在文本框接收到新值后执行，但之前 / strong>它们由事件处理程序处理。
所以，简短回答，只需将if(PostBack) return;添加到Page_Load的最顶层。
长期的答案是，在做其他事情之前，你真的需要明白这一点：https://msdn.microsoft.com/en-us/library/ms178472(v=vs.100).aspx