I created a simple control which uses an update panel with a button click trigger and yes a script manager above the control. Click the button and a label is updated with the current time and this has worked fine for 6 years
Today, I changed the page to be responsive with Bootstrap but this is irrelevant to this question.
The control was added to a page which has labels and textboxes (simple form with first name / last name).
<asp:TextBox ID="txtFirstName" runat="server" CssClass="form-control input-lg" Placeholder="Your First Name" MaxLength="20" Required="true"></asp:TextBox>
If I remove:
Required="true"
and click the button in the control the date / time updates but placing this back stops the date / time updating. I need to use both as I wish for the first name to be required but also for the time to update
Simple Example:
<asp:ScriptManager ID="ScriptManager1" runat="server" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:Label ID="lblTime" runat="server" Text=""></asp:Label>
<asp:Button ID="btnRefreshTime" runat="server" Text="Refresh Time" OnClick="btnRefreshTime_Click" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnRefreshTime" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
Code Behind:
Protected Sub btnRefreshTime_Click(sender As Object, e As EventArgs)
lblTime.Text = DateTime.Now.ToString()
End Sub
What am I doing wrong and what would I need to do to resolve it without opening the form up to abuse (script attacks) etc? I don't wish to add the following to the page directive:
ValidateRequest="false"
Thank you in advance
Probabily the button server side event is prevented to execute due to the client side validation of required = "true".
Try to change the button with somewhat else which does not trigger client side validation by design. I would try with a LinkButton.
Related
i'm trying to come up with a DateTime Picker in ASP.Net using textBox, Calendar, Button and Updatefields.
if a user clicks a button the panel with a hidden calendar will become visible, and if a user selects a date calendar's visibility will become false and he date will be assigned to textBox.
My problem comes if a user wants to change month because in this case calendar will disappear because selectionChange is being triggered.
My question is how can I fish out the changing of the month and bound the hiding of the panel only if a date is selected?
thank you very much in advance.
here are the code samples:
front part:
<asp:UpdatePanel ID="UpdatePanel2" runat="server">
<ContentTemplate>
<asp:TextBox ID="TextBox2" runat="server" />
<asp:ImageButton ID="Imbut" runat="server" ImageUrl="imagesNew/calender.png" Height="17px" Width="17px" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Calendar1" EventName="SelectionChanged" />
</Triggers>
</asp:UpdatePanel>
<br />
<br />
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:Panel ID="Panel1" runat="server">
<asp:Calendar ID="Calendar1" runat="server" Height="129px" Width="209px">
</asp:Calendar>
</asp:Panel>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Imbut" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
back part
Protected Sub Imbut_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Imbut.Click
Panel1.Visible = True
End Sub
Protected Sub Calendar1_SelectionChanged(ByVal sender As Object, ByVal e As EventArgs) Handles Calendar1.SelectionChanged
TextBox2.Text = Calendar1.SelectedDate.ToString("dd/MM/yyyy")
Panel1.Visible = False
End Sub
I struggled with a similar problem. The problem is (as you stated) on the postback the control gets reset. I never found a means to do this elegantly with asp.net controls. I was able to accomplish this using the jQuery calendar and asp:hidden field. Keeping it client side via javascript I was able to allow the user to navigate the calendar change dates etc. When a date was selected the values were set to both a textbox within the ui as well as a hidden field then on submission, the value within the textbox or hidden field was picked up server side and used (in my situation) as a filter parameter.
Hey just wondering if my syntax is wrong here
<asp:UpdatePanel ID="UpdatePanel2"
runat="server"
UpdateMode="Always">
<ContentTemplate>
<asp:textbox id="searchProductName" runat="server"></asp:textBox> <asp:Button ID="btnProductSearch" runat="server" Text="Search Product Name" CssClass="search" OnClick="ProductSearch_Click" UseSubmitBehavior="true" CausesValidation="false" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnProductSearch" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
and my OnClick method
Protected Sub ProductSearch_Click(ByVal sender As Object, ByVal e As EventArgs)
' Filter by ProductName
If searchProductName.Text.Length > 0 Then
srcProductListPerCustomer.FilterExpression = " (productName like '%" + searchProductName.Text.ToString & "%')"
productListTable.DataBind()
Else
srcProductListPerCustomer.FilterExpression = ""
productListTable.DataBind()
End If
End Sub
The problem is nothing is happening when I click on the button. The button works fine without the Ajax
Your button doesn't need to be in an UpdatePanel. The controls in a UpdatePanel should be the controls that are to be updated asynchronously. Put your UpdatePanel around the GridView you're updating, and use the AsyncPostBackTrigger in the same way.
It's best to keep UdpatePanels as small as possible; the fewer controls inside them, the less HTML will be sent back from the server (less bandwidth, faster request/response time). PostBackTriggers can refer to controls outside of the UpdatePanel with no problems.
I have a button and an image in update panel. How do I force the image refresh by clicking on the button?
update
<b>Enter the code</b>
<asp:UpdatePanel runat="server">
<ContentTemplate>
<uc:TextBox ID="txtCaptcha" runat="server" />
<asp:Button ID="btnRefreshCaptcha" runat="server" Text="Refresh the code" CausesValidation="false" onclick="btnRefreshCaptcha_Click" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnRefreshCaptcha" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
Add random value parameter to the end of your image url and change that on each update
kind of ImageUrl = baseUrl + "?" + new Random().Next()
Did you try
Sub btnRefresh_Click() Handles btnRefresh.Click
Me.Image.ImageUrl = "path to your image file"
End Sub
i used the above code but it shows the script problem in dropdown list what i gave it in master page and call them as a class files in every pages.After using the above code in my coding and i refresh the captcha it shows the overload of dropdownlist in my page and refreshment of captcha works only once after tis problem occurs i cant to refresh the captcha image in my page.
I have three radio buttons on a form - A, B, C. Each of these selections populates a dropdown list with data specific to the option. When the form loads, I set option A to be checked (as the default).
When I select buttons B or C, the AsyncPostBack triggers fine and the dropdown is populated. BUT, subsequently selecting A from either B or C does not trigger the event.
I suspect that because A was checked when the form loaded, the browser is not seeing any "change" to raise the event.
So what can be done to enable the default A button recognise it is being changed from B or C in order to raise the postback?
I have tried both setting the checked state of button A in code on inital loading of the page only (ie IsPostBack is False) and alternatively setting the checked attribute of the radiobutton in the html, with the same results. If I don't default the radio button the functionality works as expected, except I don't have the radio button and dropdown list defaulted when the page first loads.
The html...
<asp:RadioButton ID="radBook" runat="server" AutoPostBack="true" GroupName="grpArticleType" Text="Book" />
<asp:RadioButton ID="radCD" runat="server" AutoPostBack="true" GroupName="grpArticleType" Text="CD" />
<asp:RadioButton ID="radDVD" runat="server" AutoPostBack="true" GroupName="grpArticleType" Text="DVD" />
<asp:UpdatePanel ID="pnlTasks" runat="server" UpdateMode="Conditional" RenderMode="Inline">
<ContentTemplate>
<asp:DropDownList ID="dropShippingSize" runat="server" CssClass="dropdownMandatory"></asp:DropDownList>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="radBook" />
<asp:AsyncPostBackTrigger ControlID="radCD" />
<asp:AsyncPostBackTrigger ControlID="radDVD" />
</Triggers>
</asp:UpdatePanel>
The code behind...
Sub Page_Load
If Not Me.IsPostBack Then
radBook.Checked = True
End If
End Sub
Private Sub rad_CheckedChanged(ByVal sender As Object, ByVal e As System.EventArgs) _
Handles radBook.CheckedChanged, radCD.CheckedChanged, radDVD.CheckedChanged
zLoadShippingSizeDropdown()
End Sub
I had the same problem and looked for an answer for hours. This seems to have nothing to do with ViewState or anything similar, but with some kind of incompatibility of using a pre-checked RadioButton as trigger for an Async PostBack.
The work around I found is amazingly easy and worked right away; instead of using the checked=true on the mark-up or myRadioButton.Checked on the server side, I did the following:
Not setting the attribute on Mark-up and add this on the Page_Load event:
if (!IsPostBack)
{
MyRadioButton.InputAttributes["checked"] = "true";
...
}
I hope this helps and saves some people hours of hair pulling :)
I'm guessing you need to need to check if the page is a postback in your load event:
protected void Form_Load(object sender, EventArgs e)
{
if (!Page.IsPostback)
{
// Set radiobutton A...
}
}
We had the same problem and it seems you will have to set the other "checked" property for radio buttons to "false".
So please add the lines
radCD.Checked = False
radDVD.Checked = False
Are you by chance handling viewstate in your code behind as well? If so then you need to handle the AJAX version of it as viewstate can often be lost on AJAX style pages. Try putting your buttons inside the update panel and see if you get the same behaviour if the panel has it's update mode set to conditional. Don't worry about the postback triggers if you do that.
The asynch triggers are only for items inside an update panel. any item outside of a panel will doa full postback by design.
<asp:UpdatePanel ID="pnlTasks" runat="server" UpdateMode="Conditional" RenderMode="Inline">
<ContentTemplate>
<asp:RadioButton ID="radBook" runat="server" AutoPostBack="true" GroupName="grpArticleType" Text="Book" />
<asp:RadioButton ID="radCD" runat="server" AutoPostBack="true" GroupName="grpArticleType" Text="CD" /><asp:RadioButton ID="radDVD" runat="server" AutoPostBack="true" GroupName="grpArticleType" Text="DVD" />
<asp:DropDownList ID="dropShippingSize" runat="server" CssClass="dropdownMandatory">
</asp:DropDownList>
</ContentTemplate>
</asp:UpdatePanel>
WOW, I would have never thought that could be the bug. Saved many hours of frustration.
Thanks Juan going through the carppy Microsoft issue and found a solution for the rest.
I have code in an Update Panel and even though on a button click i am inserting data into a db and simply calling Updatepanel.Update() the whole page is reloaded:
Gifts.ASPX
<table style="width:100%;">
<tr>
<td>
<asp:Label ID="Label2" runat="server" Text="Gift"></asp:Label>
</td>
<td>
<asp:UpdatePanel ID="UpdatePanel3" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:TextBox ID="txtNewGift" runat="server"></asp:TextBox>
</ContentTemplate>
</asp:UpdatePanel>
</td>
</tr>
<tr>
Gifts.aspx.CS
protected void cmdAddGift_Click(object sender, EventArgs e)
{
OleDbConnection objConn = new OleDbConnection(DataSource);
Random r = new Random();
int giftID = r.Next(1200, 14000);
OleDbCommand objCommand = new OleDbCommand("Insert into Gifts (GiftID, Description) values (" + giftID + ",'" + txtNewGift.Text + "')", objConn);
ExecuteCommand(objCommand);
PopulateGifts(objConn);
txtNewGift.Text = "";
UpdatePanel3.Update();
}
Any ideas why this whole page would reload instead of just the textbox getting update?
Where is the button in the above example? Inside or outside the UpdatePanel. If it is outside you will need to add it to the triggers collection of the UpdatePanel.
Also you only need to call UpdatePanel.Update() if you are changing the content of an UpdatePanel other than the one that caused the (Partial) postback.
As a side note (and personal crusade), it is recommended that a using statement is put around your DB connection.
With the markup below, the following will happen:
btnInnerPart is inside the update panel, so it will automatically cause a partial postback
btnInnerFull will cause a full postback as it has a PostBackTrigger in the trigger collection
btnOuterPart will cause a partial postback as it has an AsyncPostBackTrigger in the trigger collection
btnOuterFull will cause a full postback as it is outside the UpdatePanel
Markup:
<asp:UpdatePanel runat="server">
<ContentTemplate>
<!-- Content -->
<asp:Button runat="server" ID="btnInnerPart" Text="Inner Part" />
<asp:Button runat="server" ID="btnInnerFull" Text="Inner Full" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnOuterPart" />
<asp:PostBackTrigger ControlID="btnInnerFull" />
</Triggers>
</asp:UpdatePanel>
<asp:Button runat="server" ID="btnOuterFull" Text="Outer Full" />
<asp:Button runat="server" ID="btnOuterPart" Text="Outer Part" />
Where is the button on Gifts.ASPX? If you put the button inside the UpdatePanel or use triggers you don't need to call UpdatePanel3.Update(); from the code behind.
Also, You need to have a ScriptManager object on your page. Do you have one?
please check tag of update panel...you have to specify the trigger controls for update panel on on which the update panel will get update