How to Access HTML Form Input from ASP.NET Code Behind

How to access HTML form input from ASP.NET code behind

If you are accessing a plain HTML form, it has to be submitted to the server via a submit button (or via JavaScript post). This usually means that your form definition will look like this (I'm going off of memory - make sure you check the HTML elements are correct):

<form method="POST" action="page.aspx">

    <input id="customerName" name="customerName" type="Text" />
    <input id="customerPhone" name="customerPhone" type="Text" />
    <input value="Save" type="Submit" />

</form>

You should be able to access the customerName and customerPhone data like this:

string n = String.Format("{0}", Request.Form["customerName"]);

If you have method="GET" in the form (not recommended - it messes up your URL space), you will have to access the form data like this:

string n = String.Format("{0}", Request.QueryString["customerName"]);

This of course will only work if the form was 'Posted', 'Submitted', or done via a 'Postback' (i.e., somebody clicked the 'Save' button, or this was done programmatically via JavaScript).

Also, keep in mind that accessing these elements in this manner can only be done when you are not using server controls (i.e., runat="server"). With server controls, the id and name are different.

How to access an input type=text from code behind in ASP NET

you can change textarea to asp:TextBox

<asp:TextBox id="txtDescrizione" TextMode="multiline" Columns="50" Rows="5" runat="server" />

html form to C# code-behind code

Here's an example of some code you could put in your button OnClick event. This POST's data to another URL.

Hopefully you can figure out what's going on in this code. Basically it is building a string (data) with all of the data from the HTML form and submitting this to the other website using HTTP POST.

Most likely you would also need to check the response back from the other website.

string remoteUrl = "https://visitor2.constantcontact.com/api/signup";

ASCIIEncoding encoding = new ASCIIEncoding();
string data = "ca=my-secrect-key&list=3&source=EFD&required=list,email&url=&email=" + Server.UrlEncode(TextBox1.Text) + "&first_name=" + Server.UrlEncode(TextBox2.Text) + "&last_name=" + Server.UrlEncode(TextBox3.Text);
byte[] bytes = encoding.GetBytes(data);
HttpWebRequest httpRequest = (HttpWebRequest)WebRequest.Create(remoteUrl);
httpRequest.Method = "POST";
httpRequest.ContentType = "application/x-www-form-urlencoded";
httpRequest.ContentLength = bytes.Length;
using (Stream stream = httpRequest.GetRequestStream())
{
    stream.Write(bytes, 0, bytes.Length);
    stream.Close();
}

How to access an HTML tag in ASP.NET code behind without postback

That doesn't cause a postback, but you can't access elements from serverside if you are not on the server. If you just want to hide them client-side you can use javascript/jQuery and/or CSS. However, elements which are Visible=false(serverside) don't exist on client-side at all.

So the runat=server doesn't cause more postbacks than without it. It just says ASP.NET that it has to create a control in server-memory, so that you are able to access it there.

But as mentioned, if you want to change the visibility on client-side without a postback you can't use Visible=false. Then use CSS either with a class or inline:

abc.Attributes.Add("style", "display:none");

or without codebehind:

<div id="abc" style="display:none"> Test </div>

Now you could access it from client-side even if it's invisible, for example to switch visibility.

How to access html control value in code behind without using runat server?

By using Request.Form["id"]` on Button_Click, you will get the value of html control

string id = Request.Form["id"]

Asp.net get contents of HTML input box

Make sure that your input is within a form element, as shown on this page:

How to access html form input from asp.net code behind

How to access html controls in code behind

Add id and runat server attributes to the input tag (see below)

<input type="text" value="Username" class="input-text autoclear"  id="Username" runat="server"/>
<input type="password" value="Password" class="input-text autoclear" id="Password" runat="server"/>

You also need to change Text to Value in your code:

protected void LoginButton_Click(object sender, EventArgs e)
{
    // Validate the user against the Membership framework user store
    if (Membership.ValidateUser(Username.Value, Password.Value))
    {
        // Log the user into the site
        FormsAuthentication.RedirectFromLoginPage(UserName.Value, RememberMe.Checked);
    }
    // If we reach here, the user's credentials were invalid
    InvalidCredentialsMessage.Visible = true;
}

You can also add a html checkbox for RememberMe

<input id="RememberMe" type="checkbox" runat="server" value ="RememberMe"/>

Now you can check the checked states by calling RememberMe.Checked

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