On the DropDownList SelectedIndexChanged, the page posts back and records the name of the developer in the radiobutton. When the user clicks the Update link on the GridView, I want the customValidator to check if the Radiobutton is empty.
<EditItemTemplate>
<table>
<tr>
<td>
<asp:DropDownList ID="_ddlAllDev" runat="server" AutoPostBack = "true" DataTextField = "Text"
DataValueField = "Value" OnSelectedIndexChanged = "ddlAllDev_SelectedIndexChanged">
</asp:DropDownList>
</td>
</tr>
<tr>
<td>
<asp:RadioButtonList ID="_rblAllDev" runat="server" AutoPostBack = "true" DataTextField = "Text"
DataValueField = "Value" OnSelectedIndexChanged = "rblAllDev_SelectedIndexChanged">
</asp:RadioButtonList>
<asp:CustomValidator ID="_valDev" runat="server" ControlToValidate = "_rblAllDev" Text = "*"
ErrorMessage="Please choose at leat one developer for this task" OnServerValidate = "AllDev_ServerValidate" />
</td>
</tr>
</table>
</EditItemTemplate>
The problem is that it looks like the CustomerValidator handler is not even being called after the user click the UPPDATE link on the GridView. I have put a break point inside the method but the method is not even being called.
protected void AllDev_ServerValidate(object sender, ServerValidateEventArgs args)
{
}
Am I missing something?
Thanks for helping.
Related
i have a Listview that i use like a gridview. inside the itemtemplate i have only a 'modifyble' field, a dropdownlist.
I would like to fire a 'Save' event when user change the dropdownlist. I know i have to set up the autopostback = true of the dropdownlist but i don't know how to fire the event because visual studio don't allow me to create the 'on change event' of the dropdownlist when it is inside a listview.
This is my code example
<asp:ListView ID="lvDmr" runat="server" DataSourceID="dsDmr" DataKeyNames="id">
<ItemTemplate>
<table style="width: 100%;" cellspacing="0" cellpadding="8">
<tr style="width: 100%;">
<td class="colonna-griglia" style="width: 5%;">
<%# Convert.ToDateTime(Eval("data_rilevazione")).ToString("d") %>
</td>
<td class="colonna-griglia">
<%# Eval("rivista")%>
</td>
<td class="colonna-griglia">
<asp:DropDownList runat="server" ID="myComboBox" DataSourceID="dsAgenti" DataTextField="customer"
DataValueField="customer" Width="150px" AutoPostBack="true">
</asp:DropDownList>
</td>
...
....
</asp:listview>
You may not get this in designer view, but if you directly add event handler it will definitely work. Following are code snippet for this.
Add OnSelectedIndexChanged="myComboBox_SelectedIndexChanged" to myComboBox.
<asp:DropDownList runat="server" ID="myComboBox" DataSourceID="dsAgenti" DataTextField="customer"
DataValueField="customer" Width="150px" AutoPostBack="true" OnSelectedIndexChanged="myComboBox_SelectedIndexChanged">
</asp:DropDownList>
Next in serverside , use following for event handler.
protected void myComboBox_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList ddlListFind = (DropDownList)sender;
ListViewItem item1 = (ListViewItem)ddlListFind.NamingContainer; // item1, is current row of Listview, which hold the dropdownlist that caused postback.
}
More help - http://forums.asp.net/t/1357900.aspx?SelectedIndexChanged+of+a+DropDownList+which+is+inside+a+ListView
protected void dropdownlist1_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList ddl = (DropDownList)sender;
ListViewItem dst = (ListViewItem)ddlListFind.NamingContainer;
DropDownList gddl = (DropDownList)dst.FindControl("dropdownlist1");
HiddenField hid_msg = (HiddenField)item1.FindControl("hidmsg");
hid_msg.Visible = true; hid_msg.Value = "Dropowntext : " + gddl.SelectedItem.Text.Trim() + " and value of dropdown is : " + gddl.SelectedItem.Value.Trim();
}
Or visit this link for more detail:
https://forums.asp.net/t/1357900.aspx?SelectedIndexChanged+of+a+DropDownList+which+is+inside+a+ListView
I have a LinkButton in an InsertItemTemplate which when clicked, should display a hidden DropDownList in the InsertItemTemplate. However, it doesn't seem to be working, but it will say, change the text of a label outside the Formview when the LinkButton is clicked. The event is firing, but the part to make the DropDownList visible in the InsertItemTemplate is not doing anything. Code is below:
.aspx:
<asp:FormView ID="formViewNewRecord" runat="server">
<InsertItemTemplate>
<asp:DropDownList ID="ddlAddSelection2" runat="server" DataSourceID="dSource1" DataTextField="Users" DataValueField="Users" AppendDataBoundItems="true" Visible="false">
<asp:ListItem></asp:ListItem>
</asp:DropDownList>
<asp:LinkButton runat="server" ID="lbAddAnother" OnClick="lbAddAnother_Click">+Add Another</asp:LinkButton>
</InsertItemTemplate>
</asp:FormView>
<asp:Label ID="Label2" runat="server" Text="Label"></asp:Label>
C#:
protected void lbAddAnother_Click(object sender, EventArgs e)
{
DropDownList addSelection2 = (DropDownList)formViewNewItem.Row.Cells[0].FindControl("ddlAddSelection2");
addSelection2.Visible = true;
Label2.Text = addSelection2.ID;
}
Your dropdown control is not an immediate child of your formview. So since the FindControl call is not recursive, you have to search for the control in the right location of your form view's child controls. See this for the details but at a high level, you need something along the lines of:
DropDownList ctrl = (DropDownList)FormView1.Row.Cells[0].FindControl("ddlAddSelection2");
After that, you should check it for null for safe measure.
So if the user selects a value from a dropDownList and clicks the button, the ID is passed to the code behind(which is where I want it)
E.g.
<asp:DropDownList ID="DropDownList" runat="server" AppendDataBoundItems="true" DataTextField="Company_Name" DataValueField="id">
<asp:ListItem Text="---Select---" Value="0" />
</asp:DropDownList>
So dataValueField will pass the 'id' of the selected record in the DD.
However On the same page I am using a repeater to display records that have been previously chosen from the drop down, Beside each record i have a 'Change Prices' button which I want to perform a task when clicked, all works fine however all I need is the same 'id'.
So is this done in a similar way? E.g
<asp:Repeater ID="repeaterShowName" runat="server">
<HeaderTemplate>
<tr>
<th>
<asp:Label ID="SubConName" Text="Current SubContractors" runat="server"></asp:Label>
</th>
</tr>
</HeaderTemplate>
<ItemTemplate>
<tr>
<td>
<asp:Label ID="SubCon" Text='<%# Bind ("Company_Name") %>' runat="server"></asp:Label>
</td>
<td>
<asp:LinkButton ID="AddNewBOQLink" runat="server" OnClick="EditPricesForSubContractor" CssClass="bottomhyperlink">Change Prices</asp:LinkButton>
</td>
</tr>
</ItemTemplate>
</asp:Repeater>
//So Do I add in DataValueField="id" inside the link button, so when the user selects the hyperlink beside the name, it will automatically have the 'id?
You should use the CommandArgument property of the LinkButton to pass the id to the method that handles the click.
So your LinkButton will now look like this:
<asp:LinkButton ID="AddNewBOQLink" runat="server" CommandArgument='<%# Bind("id")%>' CssClass="bottomhyperlink">Change Prices</asp:LinkButton>
And you want to add the following property to your Repeater:
<asp:Repeater .... OnItemCommand="repeater_Command" ...
The method that will handle the command event will look like this
void repeater_Command(Object Sender, RepeaterCommandEventArgs e) {
//retrieve the id like so
int id = (int)e.CommandArgument;
}
Also, note that I removed the OnClick property from the LinkButton. It is not needed as you are handling the click via the repeater's OnItemCommand method.
In addition, you may want to consider adding a CommandName propery to the LinkButton. This is used to identify which command you wish to execute. Currently, you only have a single command: Change Prices. But in the future you may want to add an additional button with a different command.
In order to do this, add the following property to the LinkButton:
<asp:LinkButton ... CommandName="ChangePrice" ...
And modify the repeater_Command method to handle the CommandName. Like so:
void repeater_Command(Object Sender, RepeaterCommandEventArgs e) {
switch(e.CommandName)
{
case "ChangePrice":
//retrieve the id like so
int id = (int)e.CommandArgument;
break;
}
}
I'm working with an application develop by ASP.NET, the problem I face is using FormView control, the FormView Control has ItemTemplate, InsertItemTemplate and EditItemTemplate.
Below is the code fragment of InsertItemTemplate:
<asp:FormView ID="FormView1" runat="server" DefaultMode="ReadOnly">
<InsertItemTemplate>
<table cellpadding="0" cellspacing="0">
<tr>
<td>
<asp:Label id="lblPS" runat="server" Text="Process Status"></asp:Label>
</td>
<td>
<asp:DropDownList ID="ddlPS" runat="server"></asp:DropDownList>
</td>
</tr>
<tr>
<td>
<asp:Label id="lblAP" runat="server" Text="Action Plan"></asp:Label>
</td>
<td>
<asp:TextBox id="txtAP" runat="server" Width="230px" TextMode="MultiLine" Rows="5"></asp:TextBox>
</td>
</tr>
<tr>
<td colspan="2">
<asp:Button ID="btnSubmit" runat="server" Text="Submit" onclick="btnSubmit_Click" />
</td>
</tr>
</table>
</InsertItemTemplate>
</asp:FormView>
In Page_Load event, I do DataSource Binding into the DropDownList as below:
FormView1.ChangeMode(FormViewMode.Insert);
DropDownList ddlPS = FormView1.FindControl("ddlPS") as DropDownList;
ddlPS.DataSource=GetProcessStatus();
ddlPS.DataBind();
ddlPS.Items.Insert(0, new System.Web.UI.WebControls.ListItem("- Please Select -", "- Please Select -"));
The data binding into DropDownList and the "- Please Select -" was ok.
Here the problem comes, when Submit Button click, I wanted to get user selected DropDownList Value, but the DropDownList.SelectedItem.Text always return me "- Please Select -".
Please advise how can I get the user selected value in InsertItemTemplate.
The problem is with your DataBind on Page Load event.
When you DataBind you clear the existing values and hence loose the selected value.
A drop down list remembers the items in it, so you don't need to DataBind on every postback.
Your could should be like this.
protected void Page_Load(object sender, EventArgs e)
{
if(!IsPostBack)
{
DropDownList ddlPS = FormView1.FindControl("ddlPS") as DropDownList;
ddlPS.DataSource=GetProcessStatus();
ddlPS.DataBind();
ddlPS.Items.Insert(0, new System.Web.UI.WebControls.ListItem("- Please Select -", "- Please Select -"));
}
}
I need to be able to trigger events when a user clicks on a radio button that is generated within an control on my page.
I've added an OnSelectedIndexChanged handler to the RadioButtonList and created a function in my code behind that should handle the selection of the RadioButtonList's ListItems, but I don't know how to pass a value to that function.
Here's my code:
<asp:Repeater runat="server" ID="rptQuestions">
<HeaderTemplate><table width="100%"></HeaderTemplate>
<ItemTemplate>
<tr>
<td colspan="2"><%# Container.DataItem("QuestionText")%></td>
</tr>
<tr>
<td>
<asp:RadioButtonList runat="server" ID="rblAnswerSelection" RepeatDirection="Horizontal" AutoPostBack="true" OnSelectedIndexChanged="CheckAnswer">
<asp:ListItem Text="True" Value="1"></asp:ListItem>
<asp:ListItem Text="False" Value="0"></asp:ListItem>
</asp:RadioButtonList>
<asp:Label runat="server" ID="lblCorrectAnswer" Text="<%#Container.DataItem("CorrectAnswer") %>"></asp:Label>
</td>
<td><asp:Label runat="server" ID="lblResult"></asp:Label></td>
</tr>
</ItemTemplate>
<FooterTemplate></table></FooterTemplate>
</asp:Repeater>
Private Function CheckAnswer(ByVal SelectedAnswer As Integer) As Boolean
Select Case SelectedAnswer
Case 1 ' User answered True
If lblCorrectAnswer.Text = "True" Then
Return True
Else
Return False
End If
Case 0 ' User answered False
If lblCorrectAnswer.Text = "False" Then
Return True
Else
Return False
End If
End Select
End Function
The idea is that the user is to be informed whether or not their selected answer was correct. The value of the CheckAnswer function would determine a "CORRECT" or "INCORRECT" message displaying on lblResult. If there's a way to do this without a PostBack, then that would be ideal.
Any suggestions will be greatly appreciated.
Here's brief outline of client side solution (w/o post-back). Use html radio-buttons along with a hidden field to store the correct answer. Attach click event handlers on radio-buttons to match the value with the value from hidden field.
Repeater Mark-up:
<tr>
<td colspan="2"><%# Container.DataItem("QuestionText")%></td>
</tr>
<tr>
<td class="answerContainer">
<input type="radio" class="option" name='answer_<%# Container.ItemIndex %>' value="1">True
<input type="radio" class="option" name='answer_<%# Container.ItemIndex %>' value="0">False
<input type="hidden" id="correct_answer" value='<%#Container.DataItem("CorrectAnswer") %>' />
</td>
<td>
<span class="result" />
</td>
</tr>
Java-script (using jquery):
$(document).ready(function() {
$('td.answerContainer .option').click(function() {
var opt = $(this);
var correctAns = opt.next('#correct_answer');
var result = (opt.val() == correctAns.val()) ? "Correct" : "Incorrect";
opt.parent().next('td').find('.result').html(result);
});
});
Disclaimer: untested code
Note that radio button names are suffixed with the item index so that on the server side, you can read the user's answers by looking into the request (for example, value of Request["answer_1"] should tell user selected answer for second question -> "1" : True, "0": False and empty string: no selection).
The obvious disadvantage is that correct answer is stored in the html and so it will be simpler to cheat the system. Solution can be to make ajax call to the server to check if the answer is correct or not - this will need creating salted time-bound pseudo-random tokens to identify questions (otherwise user can make same ajax calls to get answers).
Cut your RadioButton code from repeater somewhere outside repeater, go to Design view and click on that RadioButton (now it's not included in repeater and you can assign event handler to it without typing any code manually).
When you select this RadioButton in DesignView, click events button in your proporties tab and click OnSelectedIndexChanged and this will auto generate eventhandler function. You have to enable autopostback on this radiobutton (arrow in top right corner of control - in Design view).
Now cut back this RadioButton and place it inside your repeater. Now every radiobutton change will cause calling generated handler function where you can cast sender object to RadioButton, and you can access its value with SelectedValue property.
I've tried this solution many times, but only in C# so I am sorry if something is different in VB.NET
You can't use Function as an event handler. It must be a sub which takes two argument.
Take a look at this sample.
Markup
<asp:Repeater runat="server" ID="rptQuestions">
<HeaderTemplate><table width="100%"></HeaderTemplate>
<ItemTemplate>
<tr>
<td colspan="2"><%# Eval("Name")%></td>
</tr>
<tr>
<td>
<asp:RadioButtonList runat="server"
ID="rblAnswerSelection"
RepeatDirection="Horizontal"
AutoPostBack="true"
OnSelectedIndexChanged="CheckAnswer">
<asp:ListItem Text="True" Value="1"></asp:ListItem>
<asp:ListItem Text="False" Value="0"></asp:ListItem>
</asp:RadioButtonList>
<asp:Label runat="server"
ID="lblCorrectAnswer"
Text='<%#Eval("CorrectAnswer") %>'>
</asp:Label>
</td>
<td><asp:Label runat="server" ID="lblResult"></asp:Label></td>
</tr>
</ItemTemplate>
<FooterTemplate></table></FooterTemplate>
</asp:Repeater>
Code-behind
Public Class Data
Public Property QuestionText As String
Public Property CorrectAnswer As String
End Class
Dim lst As List(Of Data)
Protected Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load
If Not IsPostBack Then
lst = New List(Of Data)
lst.Add(New Data() With {.QuestionText = "A", .CorrectAnswer = "True"})
lst.Add(New Data() With {.QuestionText = "B", .CorrectAnswer = "False"})
lst.Add(New Data() With {.QuestionText = "C", .CorrectAnswer = "True"})
rptQuestions.DataSource = lst
rptQuestions.DataBind()
End If
End Sub
Protected Sub CheckAnswer(sender As Object, e As System.EventArgs)
Dim rad As RadioButtonList = DirectCast(sender, RadioButtonList)
Dim item As RepeaterItem = DirectCast(rad.Parent, RepeaterItem)
Dim correctAns As Label = DirectCast(item.FindControl("lblCorrectAnswer"), Label)
Dim result As Label = DirectCast(item.FindControl("lblResult"), Label)
Dim SelectedAnswer As String = rad.SelectedItem.Text
If correctAns.Text = SelectedAnswer Then
result.Text = "Correct"
Else
result.Text = "Incorrect"
End If
End Sub