Develop Reference

ASP.Net Checkbox conditional Attributes

I have a webform with a checkbox in it. I need to do two things differently based on an environment setting.
Add a class
Add the Text attribute so a label gets created
<% if setting == true) { %>
<asp:CheckBox ID="optionCheckbox" class="option-checkbox radio-checkbox" runat="server" Text="Label Text"/>
<% } else { %>
<asp:CheckBox ID="optionCheckbox" class="option-checkbox" runat="server"/>
<% } %>
The problem with this is the page won't render because the ids are the same, even though only one could ever get rendered. There is a lot of other processing with javascript and such so I don't want different ids for each scenario.

I was able to fix this by keeping only the "base" checkbox code below and then overriding the PreRender event to add the class and set the Text attribute there.
<asp:CheckBox ID="optionCheckbox" class="option-checkbox" runat="server"/>
Code Behind:
CheckBox optionCheckbox = this.optionCheckbox as CheckBox;
if (optionCheckbox != null)
{
optionCheckbox.Text = "Label Text";
optionCheckbox.Attributes.Add("class", "option-checkbox radio-checkbox");
}
I'd still like to know if there is a way to do this in the markup file though.

Sorry about this syntax , I don't use ASPNet webPage.
You can implement it logically..
Firstly , define class and text variable and set value for business..
Finaly set checkbox class and Text value by variable
var class = "option-checkbox";
var text = "";
if(setting == true)
{
class = "option-checkbox radio-checkbox";
text = "Label Text";
}
<asp:CheckBox ID="optionCheckbox" class="setClassProperty" runat="server" Text="SetTextProperty"/>

Unable to read hidden field value in ascx.cs page

I have a hidden field like this:
<asp:HiddenField ID="showHideFlag" runat="server" />
I am assigning some value to this hidden field in java script as follows:
function controlSearchBar() {
if ($("#MainContent_ProjectListControl_searchBar").is(":hidden")) {
$("#MainContent_ProjectListControl_showHideFlag")[0].value = "showing";
} else {
$("#MainContent_ProjectListControl_showHideFlag")[0].value = "hiding";
}
}
I am trying to read this hidden field in ascx.cs page as follows:
string hdnValue = this.showHideFlag.Value;
But this hdnValue is not getting the value of that hidden field.
Can someone help on this?

Hidden as type="hidden"
$("#MainContent_ProjectListControl_searchBar").attr('type') == 'hidden'
Hidden as display: none
$("#MainContent_ProjectListControl_searchBar").is(":hidden")

Gets the control ID for HTML markup that is generated by ASP.NET.
<asp:Label ID="SelectedSport" runat="server" ClientIDMode="Static" ClientID="showHideFlag">
javascript
$("#showHideFlag").text("found");

You are saying that you can get the value in javascript So I think the the problem is with the hidden field. try to set value by Client id as follows-
var hd = document.getElementById('<%= showHideFlag.ClientID%>');
hd.value = "hi";
And my another question is in which event you are accessing value? because If you are setting value in javascript and accessing in Page Load event then it will not work because first of all Page load event gets fired and then Javascript function executes.

How to set focus at the end of textbox while typing?

I have a textbox with a live search function. It is working all good except one problem. If I type any characters on it, it just loses its focus. If I set textbox.Focus(), the cursor goes at the beginning of the textbox.
I have tried most of solutions on the internet. Please check my codes below.
asp:TextBox ID="searchCompany" runat="server" Text="" CssClass="searchCompany" AutoPostBack="true" Width="190px" OnTextChanged="searchCompany_TextChanged"></asp:TextBox>
In page_Load
protected void Page_Load(object sender, EventArgs e)
{
//ScriptManager1.RegisterAsyncPostBackControl(Menu1);
menuDisplay();
searchCompany.Attributes.Add("onkeyup", "setTimeout('__doPostBack(\\'" + searchCompany.UniqueID + "\\',\\'\\')', 0);");
//searchCompany.Attributes.Add("onfocus", "javascript:setSelectionRange('" + "','')");
//searchCompany.Focus();
}
and I have tried javascript as below
<script type="text/javascript">
function setSelectionRange() {
var inputField = document.getElementById('searchCompany');
if (inputField != null && inputField.value.length > 0) {
if (inputField.createTextRange) {
var FieldRange = inputField.createTextRange();
FieldRange.moveStart('character',inputField.value.length);
FieldRange.collapse();
FieldRange.select();
}
}
}
</script>
I have tried to put codes on a method "searchCompany_TextChanged" which is calling if user type any characters on a textbox everytime however it is not working as well.
I saw other solutions with using Textbox.Select() but System.Windows.Control is not working in asp.net i guess.
Any idea??

There's a very simple trick that's worked for me. Basically, set the text value of the of input to itself to its own text value, and that will move the cursor to the end of the text. Then just focus it. This code uses jQuery to demonstrate that, but you should be able to do that in straight JS as well.
HTML
<input type="text" id="focusText"></input>
<button id="focusButton">Set Focus</button>
JavaScript
$("#focusButton").click(function() {
var text = $("#focusText").val();
$("#focusText").val(text).focus();
})
Here's a non jQuery example of the JavaScript, HTML should be the same:
document.getElementById("focusButton").onclick = function() {
var inputElement = document.getElementById("focusText");
var text = inputElement.value;
inputElement.value = text;
inputElement.focus();
}
Here's a fiddle demonstrating the non-jQuery version of the code: http://jsfiddle.net/C3gCa/

Error while retrieving value from multiline textbox using Jquery

I have a requirement where I have to validate for the empty text of a multiline textbox in aspx. I am using jquery for this purpose.
My aspx page would look like this:
<asp:TextBox runat="server" ID="txtClarification" ClientIDMode="Static" TextMode="MultiLine" Rows="8" Style="width: 780px;"></asp:TextBox>
and in my Jquery function:
var textbox = ('#txtClarification').val();
if (textbox.length == 0) {
//do something
}
But the statement which I retrieve the textbox value throws error:
Microsoft JScript runtime error: Object doesn't support property or method 'val'
Is there any difference in retrieving the value from a Multiline textbox?

Don't forget the $:
var textbox = $('#txtClarification').val();
//------------^
if (textbox.length == 0) {
//do something
}
Also I'm not an ASP.NET expert, but you may need to specify ClientID for your selector to work.

Change color of text box with CustomValidator

I am creating some text boxes at runtime and I would like to change the color of the text box if the text box has been left blank
and the user submits the form.
I am using the code behind approach, this is the code I wrote in the .aspx.cs file
textBoxObj is the text box object that I create at runtime and it is the object on which I want the empty validation.
CustomValidator customValidatorObj = new CustomValidator();
customValidatorObj.ControlToValidate = textBoxObj.ID;
customValidatorObj.ClientValidationFunction = "changeColorofTextBox";
and I wrote a small Javascript snippet within the .aspx file which goes as follows (I haven't yet written the logic to change the color,
just making it not valid for now)
<script type="text/javascript">
function changeColorofTextBox(oSrc, args) {
if (args.Value.length > 0) {
args.IsValid = true;
}
else {
args.IsValid = false;
}
}
</script>
In the submit button click function of the form, I have this check if(Page.IsValid), then submit the form. However, even when the text box is empty,
the form gets submitted. It seems like the function is not even being hit. Do you have any pointers on what I am doing wrong?
I am fine with either client side or server side validation, whichever works.
EDIT
I got the error, I just had to do this
customValidatorObj.ValidateEmptyText = true;
and it started working.. Thank you, I didn't realize that the customValidator class does not try validating if the control is blank.
But I am stuck again :(
In the form, I have many text boxes. Suppose, the user entered text for 3 of the text boxes and left 2 of them blank, how do I find the text box ids so that I can change the color of only the blank ones. or, how can I write code in the javascript to find out the control ID at runtime?
I know we have to do this
document.getElementById(CONTROLIDGOESHERE).style.backgroundColor = "red";
but how I get the CONTROLIDGOESHERE value to pass to the getElementById function?
Any pointers, thanks.

Try setting customValidatorObj.EnableClientScipt = True

Assuming you are running .NET Framework version 4.0 then you could declare your textboxes using ClientIDMode="Static". That way they'll have the same ID client-side and server-side e.g.
<asp:TextBox runat="server" ID="txtName" ClientIDMode="Static" />
Then you could trigger client-side validation on a button click by declaring a button like this:
<input type="submit" id="btnSubmit" onclick="ClientSideValidation(); return false;" value="Save"/>
The JavaScript function could look something like this:
<script type="text/javascript">
function ClientSideValidation() {
var txtName = document.getElementById("txtName");
if (txtName.value.length == 0) {
txtName.style.background = "#DE0000";
}
// Check other text boxes...
}
</script>

Thank you guys, I figured it out. This code does the job for me
.aspx.cs
CustomValidator customValidator = new CustomValidator();
customValidator.ControlToValidate = textBox.ID;
customValidator.ClientValidationFunction = "changeColorofTextBox";
customValidator.ValidateEmptyText = true;
customValidator.EnableClientScript = true;
e.Item.Controls.Add(customValidator);
.aspx
<script type="text/javascript">
function changeColorofTextBox(oSrc, args) {
if (args.Value.length > 0) {
args.IsValid = true;
}
else {
var ctrlid = oSrc.id;
var validatorid = document.getElementById(ctrlid);
ctrlid = validatorid.controltovalidate;
document.getElementById(ctrlid).style.backgroundColor = "Tomato";
args.IsValid = false;
}
}
</script>