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copied!<p>To ensure that the values of input fields persist across postbacks and that server events are raised:</p> <ul> <li>Use view state to keep track of dynamically created controls.</li> <li>Re-create the controls with the same IDs in <code>LoadViewState</code> (<em>not</em> <code>Load</code> or <code>PreRender</code>, because then the values of input fields will be lost).</li> </ul> <p>The rest of this answer details how I modified your code to get it to work.</p> <h2>RMAPart.ascx</h2> <p>Just for convenience, you can declare the header row in the .ascx:</p> <pre><code><asp:Table ID="Table_Parts" runat="server" CssClass="hor-zebra"> <asp:TableRow> <asp:TableHeaderCell Text="Part" /> <asp:TableHeaderCell Text="Quantity" /> <asp:TableHeaderCell /> </asp:TableRow> </asp:Table> </code></pre> <h2>RMAPart.ascx.cs</h2> <p>To keep track of dynamically created rows, maintain a list of row IDs in view state:</p> <pre><code>public partial class RMAPart : System.Web.UI.UserControl { private List<string> RowIDs { get { return (List<string>)ViewState["m_RowIDs"]; } set { ViewState["m_RowIDs"] = value; } } </code></pre> <p>In the <code>btn_AddPart_Click</code> handler, generate a new row ID and create the controls for the new row:</p> <pre><code> protected void btn_AddPart_Click(object sender, EventArgs e) { string id = GenerateRowID(); RowIDs.Add(id); CreatePartRow(id); } private string GenerateRowID() { int id = (int)ViewState["m_NextRowID"]; ViewState["m_NextRowID"] = id + 1; return id.ToString(); } private void CreatePartRow(string id) { TableRow tr = new TableRow(); tr.ID = id; TableCell tc1 = new TableCell(); TextBox tb_Part = new TextBox(); tb_Part.ID = "tb_Part_" + id; tb_Part.CssClass = "textbox1"; tc1.Controls.Add(tb_Part); tr.Cells.Add(tc1); TableCell tc2 = new TableCell(); TextBox tb_Quantity = new TextBox(); tb_Quantity.ID = "tb_Quantity_" + id; tb_Quantity.CssClass = "textbox1"; tc2.Controls.Add(tb_Quantity); tr.Cells.Add(tc2); TableCell tc3 = new TableCell(); Button btn_Delete = new Button(); btn_Delete.ID = "btn_Delete_" + id; btn_Delete.CommandArgument = id; btn_Delete.Click += btn_DeleteTableRow_Click; btn_Delete.Text = "Remove"; tc3.Controls.Add(btn_Delete); tr.Cells.Add(tc3); Table_Parts.Rows.Add(tr); } </code></pre> <p>In the <code>btn_DeleteTableRow_Click</code> handler, delete the clicked row and update view state:</p> <pre><code> protected void btn_DeleteTableRow_Click(object sender, EventArgs e) { Button btn = (Button)sender; TableRow tr = (TableRow)Table_Parts.FindControl(btn.CommandArgument); Table_Parts.Rows.Remove(tr); RowIDs.Remove(btn.CommandArgument); } </code></pre> <p>Hook <code>Page_Load</code> and start things off by creating the first row:</p> <pre><code> protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { Reset(); } } public void Reset() { while (Table_Parts.Rows.Count > 1) Table_Parts.Rows.RemoveAt(Table_Parts.Rows.Count - 1); ViewState["m_NextRowID"] = 0; string id = GenerateRowID(); RowIDs = new List<string> { id }; CreatePartRow(id); } </code></pre> <p>Override <code>LoadViewState</code> and re-create the rows using the IDs stored in view state:</p> <pre><code> protected override void LoadViewState(object savedState) { base.LoadViewState(savedState); foreach (string id in RowIDs) { CreatePartRow(id); } } } </code></pre> <h2>Dealing with Parts</h2> <p>The code above doesn't use your <code>Part</code> structure at all. To actually move data between your business objects and the user control, you can add a public method that takes a <code>Part</code> collection and uses it to create rows and populate text boxes, and then add another public method that reads out the values of the text boxes into a <code>Part</code> collection.</p>

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