I've been banging my head against this all morning, so hopefully I can get some help. Essentially I'm having issues getting values from some textbox controls I'm creating dynamically in .net 4.
Here's the desired flow of the application.
1). User selects a html document from a dropdown menu that is a template for a letter. This html document has tags of the format $VARIABLENAME$ that will be replaced with the correct values.
2). The program runs though the template and pulls out all strings of the format $STRING$ and stores them in a list.
3). For each entry in this list, the program generates an asp:label and an asp:textbox with a unique ID based on the original $VARIABLENAME$ field.
4). User enters replacement values, and hits submit.
5). Program replaces all $STRING$'s with the replacement values and outputs the result.
Everything works well up to the point where I need to get values from the text boxes. I'm quite sure it's an issue with the page lifecycle, but because the textboxes are not being generated until the use selects the desired template from the dropdown, I'm not sure how to make them persist through postbacks so I can reference them.
Am I going about this all wrong? How do I access the text fields created from a dropdown event after a postback froma submitbutton event occurs?
EDIT:
Here's the most of the relevant code.
protected void createTextBoxes(List<string> results)
{
if (results != null)
{
foreach (string result in results)
{
string formattedResult = result.Substring(1, result.Length - 2);
formattedResult = formattedResult.ToLower();
formattedResult = char.ToUpper(formattedResult[0]) + formattedResult.Substring(1);
var label = new Label();
label.ID = formattedResult;
label.Text = formattedResult + ": ";
templateFormPlaceholder.Controls.Add(label);
var textBox = new TextBox();
textBox.ID = result;
templateFormPlaceholder.Controls.Add(textBox);
templateFormPlaceholder.Controls.Add(new LiteralControl("<br />"));
previewBtn.Visible = true;
}
}
}
protected void templateDD_SelectedIndexChanged(object sender, EventArgs e)
{
var templatePath = "";
if (templateDD.SelectedIndex == 0)
{
previewBtn.Visible = false;
}
if (templateDD.SelectedIndex == 1)
{
templatePath = employeePath;
}
else if (templateDD.SelectedIndex == 2)
{
templatePath = managerPath;
}
List<string> regMatches = FindMatches(templatePath);
Session["regMatches"] = regMatches;
createTextBoxes(regMatches);
}
protected void Page_Init(object sender, EventArgs e)
{
if (Session["regMatches"] != null)
{
createTextBoxes((List<string>)Session["regMatches"]);
}
}
Later on, I'm trying to add the values from these textboxes to a dictionary. Parameters is the name of the dictionary. The key field is the $STRING$, result is what the user entered in the text box.
protected void previewBtn_Click(object sender, EventArgs e)
{
List<string> matchResults = (List<string>)Session["regMatches"];
Dictionary<string, string> parameters = new Dictionary<string, string>();
foreach (string result in matchResults)
{
TextBox tb = (TextBox)templateFormPlaceholder.FindControl(result);
parameters.Add(result, tb.Text);
}
var template = ReplaceKeys(parameters);
outputLBL.Text = template;
Here's the .aspx code.
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="offerLetter.aspx.cs" Inherits="templateRegexTesting.offerLetter" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<p>
Which template would you like to use?
</p>
<asp:DropDownList ID="templateDD" runat="server" OnSelectedIndexChanged="templateDD_SelectedIndexChanged"
AutoPostBack="true">
<asp:ListItem></asp:ListItem>
<asp:ListItem Value="1">Employee</asp:ListItem>
<asp:ListItem Value="2">Manager</asp:ListItem>
</asp:DropDownList>
<br />
<asp:PlaceHolder ID="templateFormPlaceholder" runat="server" />
<div>
<asp:Button ID="previewBtn" runat="server" Text="Preview" Visible="false" OnClick="previewBtn_Click" />
</div>
<div>
<asp:Label ID="outputLBL" runat="server"></asp:Label>
</div>
<br />
</div>
</form>
</body>
</html>
EDIT: I put this in a comment when I figured it out, but I figured I should move it into the question so it is more visible:
Thought I should update this. I feel like a bit of an idiot, but I did manage to get this working. Basically I was assigning the controls an ID equal to the replacement tokens (So ID="$FIRSTNAME$" for example). It didn't even dawn on me that the $'s would cause any issues. When I just changed to the format ID="Firstname" it works perfectly. Thank you for all of the help!
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