I'm using CalendarExtender with a textbox as the target control. My code is below:
<asp:TextBox ID="textBoxFromDate" runat="server" EnableViewState="true" />
<asp:CalendarExtender ID="textBoxFromDate_CalendarExtender" runat="server" Enabled="True"
TargetControlID="textBoxFromDate" Format="dd/MM/yyyy" EnableViewState="true">
</asp:CalendarExtender>
So I use the calendar control to set the value within the textbox. This works fine, however when a postback happens on the page the textbox value is reset to the default date for the calendar control.
How can I get the textbox to retain its value on a postback?
Thanks in advance.
I'm using ASP.Net 4.0.
did you try setting readonly field dynamically rather than in markup ? Also i'd make sure you are not resetting the value in Page_Load() during postbacks.
Or what about trying somehting like this on Page_load , also checking to see if there is a valid date in box before attempting to set it to the calendar extender selected date ?
if (IsPostBack)
{
MyCalendarExtender.SelectedDate =
DateTime.ParseExact(MyTextBox.Text, MyCalendarExtender.Format, null);
}
Related
Got weird problem. I have simple page with TextBox:
<asp:ScriptManager runat="server" />
<asp:UpdatePanel runat="server">
<ContentTemplate>
<asp:TextBox ID="amountTextBox" runat="server" TextMode="Number" />
<asp:Button runat="server" Text="Confirm" OnClick="confirmButton_Click" />
</ContentTemplate>
</asp:UpdatePanel>
After Button click I try to get TextBox value:
public partial class test : Page {
protected void confirmButton_Click(object sender, EventArgs e) {
var answer = amountTextBox.Text;
}
}
but it's empty. If I remove UpdatePanel, I manage to get the value. If I leave UpdatePanel and remove TextMode property, I manage to get the value. But why can't I have TextBoxt with TextMode set to Number in UpdatePanel?
It is a known issue, a fix is available in .NET 4.5 RTM.
Description
HTML5 has new types for the input tag, such as type="number", which is
needed to make mobile phones display a numerical keyboard instead of a
text keyboard. When doing a full postback of the page it works in all
browsers. But if I puts these in an updatepanel on a website to do a
partical postback, then none of the new HTML input types are included
in the postback response to the server from those browsers that
understands these new types (Safari/WebKit and Opera). It works
correctly in IE8 and Firefox 4, but probably only because they have
not implemented these new types and falls back to understanding it as
a type="text" field.
Here is another question with this issue and workarounds: UpdatePanel with input type other than text in html5.
I've got a date picker field declared within a template field in a GridView as follows:
<asp:TemplateField HeaderText="Shipping Date">
<ItemTemplate>
<asp:Label ID="lblShippingDate" runat="server" CssClass="dnnFormLabel"
AssociatedControlID="ShippingDatePicker" />
<dnn:DnnDatePicker runat="server" ID="ShippingDatePicker" />
</ItemTemplate>
</asp:TemplateField>
I can select the date just fine and it appears in my label control - I then click on a standard asp:Button which finds the selected row and despite it finding all the other controls on the row including the label control displaying the selected date, the label's Text attribute is blank:
var txtShippingDate = row.Cells[7].FindControl("lblShippingDate") as Label;
Please note that I'm using the DotNetNuke dnn:DnnDatePicker control but this is actually a RadDatePicker under the covers.
Can anyone suggest how I can successfully read the value?
Thanks for looking :)
Try following after you find label:
if(txtShippingDate != null) {
string date = Request.Form[txtShippingDate.UniqueID].ToString();
}
I have a form with a dropdownbox two listboxes and two buttons on it.
I removed a "select" button as I just used the DropDownList1_SelectedIndexChanged, but the event would not fire until I used the suggestion from:
Why DropDownList.SelectedIndexChanged event does not fire?
It involved changing the AutoPostBack='true' and EnableViewState="true" properties
So now the DropDownList works but with the two listboxes, the SelectedIndex stays as -1 and does not change even when selected.
Listbox code:
<asp:ListBox ID="ListBox1" runat="server" EnableViewState="true"
Height="207px" Width="168px"></asp:ListBox>
DropDownList Code:
<asp:DropDownList ID="DropDownList1" runat="server" EnableViewState="true"
AutoPostBack="true" style="font-weight: 700; margin-left: 26px">
Button click event code:
If (ListBox1.SelectedIndex < 0) Then 'No user selected
MsgBox("Please select a user to add from the Listbox on the left.", vbCritical, "ListBox2 Validation Error")
Else
The MsgBox now always says no user has been select but there is a user select, very weird.
Any ideas? I think it has something to do with post backs, page_load or the selectedindex changed event of the listbox, it worked perfectly before I made the modifications.
The problem was the postback and that the code to populate the listboxes was in a dropbox_load subroutine. This meant that the listbox would repopulate everytime something changed on the page and hence the selecteditem index would revert back to -1.
Im sure this is a very simple and easy to answer question but I've been looking at this too long and being new to ASP I cant seem to find a solution that works.
I have an ASP calendar extender, I click it and the calendar displays as expected, the selected date appears in the textbox, but when the page then posts back I cant get the selected date value from either the textbox.text or the calendarextender.selecteddate properties, I tested this by trying to assign these values to a string variable in the page_load event.
Am I missing something here?
Here is my code so far:
I have the script manager declared at the start of my form
<cc1:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server"/>
Then my textbox / datepicker within table lower down
<asp:TextBox ID="DateChooser"
runat="server"
ReadOnly="true"
style="text-align: center" Width="85px"
OnTextChanged="DateChooser_TextChanged"
AutoPostBack="true" />
<div style='position:relative; z-index:1'>
<cc1:CalendarExtender CssClass="cal_Theme1"
ID="DateChooser_CalendarExtender"
runat="server"
Enabled="True"
TargetControlID="DateChooser"
PopupPosition="Right"
Format="dd MMM yyyy"
/>
</div>
</td>
Since you have set textbox ReadOnly to true it lose changes performed by client-side code on postback. Follow this link for more detailed explanation: TextBox.ReadOnly Property Consider to set readonly attribute on textbox by client code.
Basically, I just want allow select dates greater than today. I'd prefer this way to avoid show alert messages.
I don't think that it is supported in the current version of the Toolkit to restrict selectable dates. This is a simple workaround handling the ClientDateSelectedChanged-Event and validate the selected date:
How to make sure user does not select a date earlier than today or greater than today
There could be instances where you do not want the user to select a day earlier than the current date. For example: when you are providing the user a form to book tickets, you would not like him to choose an earlier date. To achieve this requirement, use the following javascript code.
Prevent the User from selecting a Date Earlier than today
<head runat="server">
<title>Calendar Extender</title>
<script type="text/javascript">
function checkDate(sender,args)
{
if (sender._selectedDate < new Date())
{
alert("You cannot select a day earlier than today!");
sender._selectedDate = new Date();
// set the date back to the current date
sender._textbox.set_Value(sender._selectedDate.format(sender._format))
}
}
</script>
</head>
Call the code:
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server" />
<div>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<cc1:CalendarExtender ID="CalendarExtender1"
runat="server" OnClientDateSelectionChanged="checkDate" TargetControlID="TextBox1" />
</div>
</form>
Select Date Greater than today
In the javascript, just change this line
sender._selectedDate > new Date()
Note: You may argue that the user can still change the date by typing into the textbox or entering an invalid date. Well that can be easily handled using a ValidationControl and is covered in the next tip.
Add validation to the CalendarExtender Control
A simple way to add validation to the Calendar is to add a ValidationControl to the textbox associated with a CalendarExtender. You have two choices:
Add an Extender to the ValidationControl. To do so, drag and drop a ValidationControl > click on the smart tag of the ValidationControl > choose Add Extender. From the Extender Wizard, choose ValidatorCalloutExtender. Using this approach makes it extremely easy to discover and attach control extenders to your controls. In VS 2005, you had to do this process manually, by wiring up control extenders.
You can choose not to add the Extender.
We will go ahead with option A. We will be adding two ValidationControls to the TextBox. The first, a CompareValidator to check if the user does not enter an invalid date (Eg: May 32) and second, a RangeValidator to keep the date range as desired.
Adding CompareValidator
<asp:CompareValidator ID="CompareValidator1" runat="server"
ControlToValidate="TextBox1" Display="Dynamic" ErrorMessage="Invalid Date"
Operator="DataTypeCheck" Type="Date">
</asp:CompareValidator>
<cc1:ValidatorCalloutExtender ID="CompareValidator1_ValidatorCalloutExtender"
runat="server" Enabled="True" TargetControlID="CompareValidator1">
</cc1:ValidatorCalloutExtender>
Adding RangeValidator – We will restrict the user to select a date range starting from today to 15 days from now.
<asp:RangeValidator ID="RangeValidator1" runat="server"
ControlToValidate="TextBox1" ErrorMessage="RangeValidator"
Type="Date">
</asp:RangeValidator>
<cc1:ValidatorCalloutExtender ID="RangeValidator1_ValidatorCalloutExtender"
runat="server" Enabled="True" TargetControlID="RangeValidator1">
</cc1:ValidatorCalloutExtender>
In the code behind of your page, add this code
C#
protected void Page_Load(object sender, EventArgs e)
{
RangeValidator1.MinimumValue = System.DateTime.Now.ToShortDateString();
RangeValidator1.MaximumValue = System.DateTime.Now.AddDays(15).ToShortDateString();
}
VB.NET
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
RangeValidator1.MinimumValue = System.DateTime.Now.ToShortDateString()
RangeValidator1.MaximumValue = System.DateTime.Now.AddDays(15).ToShortDateString()
End Sub
Well those were some tips associated with the CalendarExtender. As future versions of the toolkit are released, we should be hopeful that there will exist easier ways, of achieving this functionality.
From: http://www.dotnetcurry.com/ShowArticle.aspx?ID=149
Another advanced approach would be to extend the CalendarExtender javascript, but then you have your own custom version of the ajax toolkit.
http://codegoeshere.blogspot.com/2007/06/extending-calendarextender.html
set StartDate property of the calender extender to DateTime.Now.Date in the page load
this will show the previous dates as unselectable