autofill textbox based on user input - asp.net

Question

I'm extremely new to ASP.NET and came across a problem I have yet to figure out. On my Default.aspx page, I have a place where users can signup. This just takes to fields - Email and Password. When the submit button is clicked, they are taking to Signup.aspx, which shows a bigger signup form with fields for username, email, password, confirm password, etc. I would like to auto fill my email and password textboxes with those of the Default.aspx page that the user has entered. Is this possible? I'm using Microsoft Visual Web Developer 2010 Express.

Answer 1

There are multiple ways to do that.
One way is to use querystring to navigate to like :
http://example.com/Signup.aspx?email=value1&password=value2
and get value on Signup.aspx Page_Load event like :
String email = Request.QueryString["email"];
String password = Request.QueryString["password"];
and assign to your text box controls like:
txtEmail.text =email;
txtPassword=password;
But posting password as clear text in query string is not good practice.
Other way is to get HTTP POST information from the source page:
In the source page, include a form element that contains HTML elements (such as input or textarea) or ASP.NET server controls (such as TextBox or DropDownList controls) that post values when the form is submitted.
In the target page, read the Form collection, which returns a dictionary of name/value pairs, one pair for each posted value. e.g.
//
void Page_Load(object sender, EventArgs e)
{
System.Text.StringBuilder displayValues =
new System.Text.StringBuilder();
System.Collections.Specialized.NameValueCollection
postedValues = Request.Form;
String nextKey;
for(int i = 0; i < postedValues.AllKeys.Length; i++)
{
nextKey = postedValues.AllKeys[i];
if(nextKey.Substring(0, 2) != "__")
{
displayValues.Append("<br>");
displayValues.Append(nextKey);
displayValues.Append(" = ");
displayValues.Append(postedValues[i]);
}
}
Label1.Text = displayValues.ToString();
}
Best & easiest I think is to use Session:
on Submitbutton_click event of Default.aspx, save values to Session like:
Session["Email"] = txtEmail.text;
Session["Password"]=txtPassword.text;
and retrieve values on Signup.aspx Page_load event like:
string email = (string)(Session["Email"]);
string password = (string)(Session["Password"]);
& assign to your control/textbox like:
txtEmail.text =email;
txtPassword=password;
There are more ways too to retrieve value from previous page like PreviousPage.FindControl("txtEmail") but I never like them.