What is use of ClientIDMode attribute in asp:CheckBox control? I found the values AutoID, Inherit, Predictable, and Static for that.
Mainly I am looking for how it is rendered in HTML? Can anyone explain about the attribute and the values?
It is how MS calculates ID of a .net control name itself. MSDN
Since ASP.net pages are put together on a server and sent to the client MS Will name the ids, based off of a variable amount of conditions, are they in a master page , are they in a user controller, a repeater, and so on.
Since you cannot have duplicate ids what do you do with a .net control that is put inside of a repeater? You need to have a naming algorithm for it. Some people foolishly use the rendered ID (ct100_*) instead of using getElementID to manipulate the element through javascript. I dont know why they exposed these algorithms instead of just saying everything is going to be 1 algorithm. Maybe someone has the answer to why they exposed the different algorithms.
Example of id generation:
Web form:
<script runat="server">
protected void Page_Load(object sender, EventArgs e)
{
lstMain.DataSource = new string[] { "a", "b" };
lstMain.DataBind();
}
</script>
<asp:Content ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
<asp:ListView ID="lstMain" runat="server">
<ItemTemplate>
<asp:CheckBox ID="chkFour" runat="server" ClientIDMode="AutoID" />
<asp:CheckBox ID="chkFive" runat="server" ClientIDMode="Predictable" />
<asp:CheckBox ID="chkSix" runat="server" ClientIDMode="Static" />
</ItemTemplate>
</asp:ListView>
</asp:Content>
Result:
<input id="ctl00_ContentPlaceHolder1_lstMain_ctrl0_chkFour" type="checkbox" name="ctl00$ContentPlaceHolder1$lstMain$ctrl0$chkFour" />
<input id="ctl00_ContentPlaceHolder1_lstMain_ctrl0_chkFive_0" type="checkbox" name="ctl00$ContentPlaceHolder1$lstMain$ctrl0$chkFive" />
<input id="chkSix" type="checkbox" name="ctl00$ContentPlaceHolder1$lstMain$ctrl0$chkSix" />
<input id="ctl00_ContentPlaceHolder1_lstMain_ctrl1_chkFour" type="checkbox" name="ctl00$ContentPlaceHolder1$lstMain$ctrl1$chkFour" />
<input id="ctl00_ContentPlaceHolder1_lstMain_ctrl1_chkFive_1" type="checkbox" name="ctl00$ContentPlaceHolder1$lstMain$ctrl1$chkFive" />
<input id="chkSix" type="checkbox" name="ctl00$ContentPlaceHolder1$lstMain$ctrl1$chkSix" />
Pass id to JS:
<script type="text/javascript">
var autoId = '<%=someControl.ClientID%>';
var predictableId = '<%=someControl.ClientID%>';
var staticId = 'someControl';
</script>
Related
i have a textbox and a button in my aspx file,i want to get the textbox value to code behind while clicking the button,I implemented this before,but now iam using asp:content pages,but now i cant get the value to codebehind
my aspx
<%# Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="test.aspx.cs" Inherits="test1.test" %>
<asp:Content ID="Content1" ContentPlaceHolderID="HeadContent" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<body>
<div>
<input type="text" runat="server" id="abc" />
<asp:Button
ID="Button1"
runat="server"
Text="Search"
class="btn"
OnClick="Button1_Click"
/>
</div>
</body>
</asp:Content>
My aspx.cs
protected void Button1_Click(Object sender,
System.EventArgs e)
{
string txtboxvalue = Request.Form["abc"];
}
but i cant get the textbox value in button click.
Since you have already given runat to your input control,
<input type="text" runat="server" id="abc" />
You can access the value of text like this
string txtboxvalue = abc.Value;
//Here no need of using Request.Form since input is now a server control
Your control doesn't have a name, so it doesn't get POSTed in the form that you can read it as Request.Form["abc"]. WebForms will generate its name, something like master00$formName$abc. You can check this in the HTML source, but it may be different per request or change after you add more controls on the page. So you should not use this field when it's autogenerated.
Either give it a name:
<input type="text" runat="server" id="abc" name="abc" />
Or, because it's runat="server" and has an id, you can simply access it from code behind:
string textBoxValue = abc.Value;
I would like to put a form on my page. There will be an input box and a submit button. When the user enter a specific id then i will take that id put it in a url and display the result from that url.
Let say user enter this: 12345678.
Then i want to take that id display the result from
http://foo.com/servlet/AccessModule?id=12345678&doc_type=pdf&sort1=capturedate&response=A on my page using asp.net technologies.
I already tried a couple of things but couldnt figure this out.
Can you please comment.
Here is how it could work. This needs some polishing but you should be able to bring it to completion yourself.
Copy this into .aspx page
<form id="form1" runat="server">
<div>
<asp:TextBox runat="server" ID="txtInput"></asp:TextBox><br /><br />
<asp:Button runat="server" ID="btnSubmit" Text="Submit"
onclick="btnSubmit_Click" /><br /><br />
<asp:Label runat="server" ID="lblResult" Text=""></asp:Label>
</div>
</form>
And this into code behind (I’m assuming you’re using C#)
protected void btnSubmit_Click(object sender, EventArgs e)
{
System.Net.WebClient wc = new System.Net.WebClient();
lblResult.Text =
wc.DownloadString(string.Format("http://foo.com/servlet/AccessModule?id={0}&doc_type=pdf&sort1=capturedate&response=A", txtInput.Text));
}
<form action="www.foo.com/search" method="get">
ID: <input type="text" name="id"><br>
<input type="submit" value="Submit">
</form>
When you send an http request it reaches the server on port 8080. You can not specify the port that you are going to use.
To pass parameters in URL you have to use this
repsonse.redirect("AccessModule.aspx?id=12345678&doc_type=pdf&sort1=capturedate&response=A");
i have this code in my default aspx file :
<body>
<form id="form1" runat="server">
<div>
<asp:PlaceHolder ID="holder1" runat="server">
<asp:Label ID="label1" runat="server" Text="Label">
</asp:Label>
<input type="text" ID="txt" runat="server"/>
<asp:TextBox ID="txt2" runat="server"></asp:TextBox>
<asp:Button Text="Ok" ID="btnOk" runat="server" onclick="btnOk_Click" />
</asp:PlaceHolder>
</div>
</form>
</body>
and my code behind is :
TextBox tb1 = holder1.FindControl("txt") as TextBox;
Response.Write(tb1.Text);
TextBox tb2 = holder1.FindControl("txt2") as TextBox;
Response.Write(tb2.Text);
my problem is here that findcontrol ("txt") return null value!!! because i used <input> ,how can i handle this control ?
Firstly, you don't need the holder1.FindControl as you can access the controls directly.
To get the input control, use the code;
HtmlInputText tb1 = this.txt;
Response.Write(tb1.Value);
You might need to import System.Web.UI.HtmlControls.
Using System.Web.UI.HtmlControls;
Edit
To find controls which have been dynamically added via Javascript, you will need to use the Request object.
string theValue = Request.Form["txt"].ToString();
An input type="text" is not a TextBox. So you either should cast it to HtmlInputText or use a TextBox instead.
var txt = (HtmlInputText)row.FindControl("txt");
Note that you need to add using System.Web.UI.HtmlControls,
MSDN :
Control.FindControl : Method Searches the current naming container for
the specified server control.
as is not server control it is not pissible to find it ! any Other Way to handle controls that are not server side ?
what happen if any one want to get text of text box that is not run at server .
Hello all how to use HTML text field instead of ASP.NET textbox.?
How to write C# code to make use of HTML forms instead of ASP.NET
EDIT:
<form id="form1" runat="server">
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<input id="Text1" type="text" runat="server" />
<asp:Button ID="Button5"
runat="server" Text="Button" OnClick="button5_click" />
<div>
<script runat="server">
protected void button5_click(object sender, EventArgs e)
{
Text1.Value = "Hello";
}
</script>
</form>
Instead of using or whatever server control, just type in the standard type tags or whichever HTML control you want.
If you want to be able to access them from your code-behind, then just include a runat="server" value with each HTML tag and make sure you give it an ID.
You need to retrieve the value from the HTTP request's Form collection:
<input type="text" name="MyTextField" />
Code behind:
string value = Request.Form["MyTextField"];
This question doesn't make much sense. You really should clarify and flesh out the question and explain what you are trying to do.
In some ways, an ASP.NET textbox is an HTML text field that C# code can make use of. So what's the problem with an ASP.NET textbox?
You can create an instance of a HtmlInput control in code, or alternatively add a runat="server" attribute to an <input> element in your aspx file, you can then access this from server-side code using it's ID.
As an alternative, you may wish to take a look at http://asp.net/mvc to get better control of your HTML markup.
I have a website where i want to implement search functionality.So i added the below code to have a search box in my html page
<form id="search" method="post" action="Results.aspx">
<input id="txtSearchKey" type="text" name="txtSearchKey" />
<input id="Submit1" type="submit" value="submit" /><br />
<br />
</form>
In Results.aspx, I want to read the value user has entered in the txtSearchKey text box. What is the ideal way to do this ? I used
string strKey = Request.Form["txtSearchKey"].ToString();
But it throw a null reference exception.
I don't want to have all pages in ASP.NET.I want to have only the result page as ASP.NET
Could be because you do not have a NAME attribute on the textbox field. That's the value that is used as the key in the Request.Form collection. An input field without a name attribute will not be submitted, I think.
e.g.:
<input id="txtSearchKey" type="text" name="txtSearchKey" />
You can get your txtSearchKey field by this :
string strKey = PreviousPage.Request.Form["txtSearchKey"].ToString();
But, instead of using form action to forward your search to another page, you can use a button with PostBackUrl property like that :
<asp:Button runat="server" ID="btnSearch" PostBackUrl="Search.aspx" />
Because in ASP.NET, to have more then one form is not allowed.
Is there any reason you don't use
form runat="server"
and then drag a TextField and a Button in this form. Then doubleclick the button and write code you want.
If you want to do it your way you need to give your s a name="txtMySearchKey" for it to work
The way you are going about things is not really the way you work in ASP.NET web forms. The preferred way is to use asp.net server controls and events to abstract the process you are trying to achieve. For instance, your form should really be something like this (note the runat="server" attribute that enables you to reference the controls programmatically):
<form id="form1" runat="server">
<div>
<asp:Panel ID="PanelSearch" runat="server" DefaultButton="ButtonSubmit">
<asp:TextBox ID="TxtSearchKey" runat="server" /><br />
<asp:Button ID="ButtonSubmit" Text="Submit" runat="server"
onclick="ButtonSubmit_Click" /><br />
</asp:Panel>
</div>
</form>
Then, in your code behind you would handle the ButtonSubmit_Click event like this to enable you to get the value from the TxtSearchKey textbox:
protected void ButtonSubmit_Click(object sender, EventArgs e)
{
string strKey = TxtSearchKey.Text;
}
See the Quickstart example for the TextBox control for more info.
Just do not use .toString() after the Request.form... it will not give a null reference after that.