Handle OnClick in C# or JQuery - c#

I am working on a webforms project using c#/aspx/jquery. I'm not sure where to handle my Onclick. Both options (doing it in C# or jquery) seem feasible. Which would be better practice?
Here is the scenario:
I want to build a checkbox which will toggle a textbox's textmode, altering it between Password and SingleLine.
Currently, I have this following code for my markup since I am currently handling it in C#:
<asp:Checkbox ID="CheckBox1" OnCheckedChanged="CheckBox1_OnCheckedChanged"/>
The code:
protected virtual void OnCheckedChange(EventArgs e)
{
If (CheckBox1.TextMode == TextMode.Password)
CheckBox1.TextMode = TextMode.SingleLine;
else
CheckBox1.TextMode = TextMode.Password;
}
The use case of this is: A user is entering his password. On the same page, he may choose to keep the password hidden or not by checking the checkbox.

Which would be better practice?
What is your functional requirement?
Setting this in C# on the asp.net code behind, you will need a post-back to make it work. This means the page will refresh and the text box will change.
On the client (JS/JQuery) the page will not refresh.
Now you evaluate the work required vs the quality you need. (If you want a nice user experience and are ok with writing JS put it in JS, if you're strapped for time and are ok with the refresh then do it on asp.net).
I'm trying to answer your question in general sense about HOW such a decision (in my humble opinion) should be made. Realistically this is very simple to implement in javascript and your should do it there.
Now for the code (I assume you know how to put it in asp.net code behind so I'm going to write the JS approach):
Html:
My Password: <input type="password" id="mytext" /> <br />
Hide Chars : <input id="passChk" type="checkbox" checked="true" />
Javascript:
$(function() {
$("#passChk").change(function(){
if(this.checked) {
$("#mytext").attr("type","password");
} else {
$("#mytext").attr("type","text");
}
});
});
See it running here: http://jsfiddle.net/rC5NW/2/

After trying to implement the accepted answer, I realized that some browsers (I used Google Chrome) does not allow changing the type attribute. There is a way to bypass this but I don't think it is worth it for my purposes:
Therefore, It might be better to just use C#.
Relevant Questions
Does javascript forbid changing the input type from password or to password?
change type of input field with jQuery

Related

C# - How to change value of textbox on focus

I'm writing an application in C#. I would like to replace the value for the TEXT property after the user clicks (focuses) on a textbox. I would like to set the TEXT value to be blank instead of the words "ENTER NAME HERE" when they click to edit the textbox.
Front-end:
<asp:TextBox Text="ENTER NAME HERE" OnClick="MyTextboxID_OnClick" ID="MyTextboxID" runat="server"></asp:TextBox>
Code-behind:
protected void MyTextboxID_OnClick(object sender, EventArgs e)
{
MyTextboxID.Text = "";
}
I tried to find the answer to this question but the answers didn't quite match what I wanted to do.
I was hoping C# had something similar to Javascript's "OnClick" or "OnFocus" events. I added the OnClick event to the textbox for illustration purposes. This OnClick event doesn't work.
Thank you in advance for your help!
Remember that ASP.NET is primarly server-side. Actions that run in C# require a post-back to the server. The impact of this on a page can be mitigated somewhat by using AJAX, but this is why you don't see an "OnClick" event off the ASP control.
However, you can still use the Javascript "OnClick" event. Since Javascript runs on the client, and the interaction in this instance is entirely handled on the client, you should just use that.
If you are not comfortable using Javascript, you might want to look at TextBoxWatermark server side control.
It is available NuGet.
<asp:TextBox OnClick="MyTextboxID_OnClick"
ID="MyTextboxID" runat="server">
</asp:TextBox>
<ajaxToolkit:TextBoxWatermarkExtender ID="TBWE2" runat="server"
TargetControlID="MyTextboxID"
WatermarkText="ENTER NAME HERE"
WatermarkCssClass="watermarked" />
You should simply use the following Placeholder="Enter text here."
Option One:
<asp:Textbox id="txtName" runat="server" placeholder="Enter name here." />
Option Two:
$("#<%= txtName.ClientId %>").setAttribute('placeholder', 'Enter name here.');
$("#<%= txtName.ClientId %>").attr('placeholder', 'Enter name here.');
For the Javascript implementation, you would simply place that in your View and wrap it in: <script type="text/javascript"></script>. Those are the ideal approaches to display text which clears on focus.
You could also utilize the Tooltip. Hopefully these examples assist you. Important note, I have no issues with compatibility in IE 8 with the Placeholder. Also these approaches won't force a Postback which can occur due to Server-Side. Which would force you to either do a Postback or implement a Update Panel / Ajax to hide the Postback.
Plugin: https://github.com/mathiasbynens/jquery-placeholder
Why don't you use the place holder attribute and not have to worry about replacing the text at all. This would show when the text box is empty but disappear on focus

Moving text in .Net without refreshing page

I am still new to the coding field and am having a bit of trouble with a part, hoping someone can help me. I am working on a MVC page where i am trying to move text, the user inputs, around the page to a few pre-set spots and without having to refresh the page. Do i need a type of script for this? And if i do what would be best? Thanks for the help.
You can do it this way.
Enter Text here... <input id="testText" type="text" onKeyUp="javascript:showText($(this), event);"/>
<br/>
<br/>
<br/>
See it here... <span id="testTextSpan"></span>
Then, add this script...
<script type="text/javascript">
var showText = function (el, e) {
$('#testTextSpan').html(el.val());
};
<script>
See it here in this JSFiddle...
http://jsfiddle.net/ZEcNp/
Be sure to include JQuery libraries in your project, or reference the CDN.
If you'd like me to include an example with raw javascript, with no JQuery, I can also provide that for you.
I would recommend jQuery to do all that client-side.
You would just need an ID for each element you would use as the predefined spots, using either .appendTo, .insertAfter, .html, or something else depending on your exact needs.

how to open modal popup on textbox click in c#

I have a TextBox and and I want to open a Popup on clicking TextBox. There is no Click event for TextBox. I want to do it in C# completely. I don't need jquery in opening Popup on Click of TextBox.
Asp.net textbox:
<asp:textbox onclick="myJavaScriptFunction()" runat="server" id="myTextBox" ... >
#edit
jquery example:
$("#target").click(function() {
alert("Handler for .click() called.");
});
The nature of creating a website solution like you are doing makes this impossible. In ASP.NET WebForms and MVC you do not deliver C# code to the user so you cannot create client side behavior with C#; instead, you deliver an HTML page and assets like files for Javascript, CSS, images, etc. If you want to invoke client side behavior, you need code that will run client side. That means using Javascript, and I recommend that you use jQuery while doing that.
nirmus's answer will give you an example for that, but to answer your question completely bluntly the answer is: "You can't."

C#.NET coming from PHP

I am coming from PHP so bear with me with my noobness...
I want to know a few things.
I know PHP, javascript and MySQL very very well now and I understand that browsers understand a few things.. html and javascript.
I ran through a tutorial of c#.net and found that it had pre-made "user controls" and i thought, oh my it's completely different from PHP... Then i realised that in the end it ends up with a bunch of javascript I could have written myself (not saying i want to ;), just saying).
My questions....
1.
If I have a table with some input fields:
<form id="form1" runat="server" method = "post" action = "validate_entry.aspx">
<table>
<tr>
<td>Name: </td><td><input type = "text" name = "name" /></td>
</tr>
<tr>
<td colspan = "2"><input type = "submit" value = "submit" /></td>
</tr>
</table>
</form>
and use the post and action methods, and then in validate_entry.aspx on Page_Load class I call something like:
c.Request["name"];
and do whatever with it.. Is this still a professional way of using c# or am i wanting it to be too much like PHP. Am i missing out on some execute speed or something even though it's running javascript.
2.
If I wanted to simply output the word "arse" in a div... If I do something like this, am I defeating the object of c#.net
<div id = "the_butt_holder">
<% Response.Write("arse"); %>
</div>
or a better example is that in my validate_entry.aspx page I do:
<div id = "the_response">
<% Response.Write(c.Request["name"]); %>
</div>
I think in your case, you would benefit greatly from looking at ASP MVC. It gets much closer to the grain and will probably be much closer to what you're used to working with as you have a great deal of control over the html.
Well James, I think you could start using asp.net mvc. It will be so easier to you than asp.net webforms. WebForms is based on Server Controls and Events, you cannot set a page in tag, instad of it you can create a , double click in it and write your code on .cs file respective of your webform, then, the .net framework will do a thing called PostBack and executes this event. There's a desnecessary long life cycle when a PostBack runs.
In Asp.Net webForms you don't have control of your output HTML code. The SErver Controls will do it for you, and sometimes it is not you want (or need).
With ASP.NET MVC you have a Route Tables and you have a MVC Architecture Pattern, so, if you use a mvc framework in PHP, it would be easy for you. With ASp.NET MVC you have control of your HTML, and you can create Typed Views. Check this link: http://www.asp.net/mvc
I hope it helps you.
Your way is by no means wrong, however there is another way in ASP.NET, which is to use actual TextBox (which renders input field) control instead of input field directly. That way, you will be able to access value as a property of the control.
<asp:TextBox id="tb1" runat="server" />
var text = tb1.Text;
Why not just write literal directly instead of outputting it like this?
<div id = "the_butt_holder">
arse
</div>
You may feel much more at home using ASP.NET MVC, and Razor layout engine. It's much more like PHP and Smarty (or whatever similar templating engine replaced it nowdays :) )
You can find more than enough tutorials right there on the site to get you started.

calling a javascript function in C#

Hi i wanted to show or hide duplicate records according to query. So, I need to know how to call the javascript function from C# codebehind.
<a onclick="Grid1.insertRecord(); return false;" id="a2" href="javascript:">Save</a>
When I click save i need to show a popup which i have written in javascript.
if (!exist)//exists is the query
{
System.Web.UI.Control my = FindControl("a2");
a2.Attributes.Add("onclick", "retrun HideDuplicate()");
This line returns an error saying "a2 doesnot exist in current context."
Why not use an asp.net LinkButton? It has a server side Click event and is accessible from c# code-behind.
The basic <a> tag is not turned into a control by asp.net unless you add a runat="server" to it. Its then turned into a HtmlGenericControl.
<a onclick="Grid1.insertRecord(); return false;" id="a2" href="#" runat="server">Save</a>
This might work for you - its not clear if you have more than one of these links on the page (such as in a row of a gridview?) or if its just on there once.
Also the way you have used javascript is not following best practices but thats a discussion for another day :)
MSDN documentation for programatic creation of client side callbacks without postback with an example where the code behind is in C# might give a good overview of how it is supposed to work in general.
In your case, the corresponding code-behind should implement the interface 'ICallbackEventHandler' and the two methods it describes. In addition, you would need two more client side Javascript functions to prepare and handle the callback, besides the executor/invoker (in your case, a 'save' method). However one of the additional two Javascript functions could be registered in the codebehind, as the example shows.

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