Databases
StackOverflow2013
Postsdbo
POGetting Error On Javascript document.getElementById('name'). RETURNS NULL
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POGetting Error On Javascript document.getElementById('name'). RETURNS NULL
    primarykey
    data
    text
    <p>I need to execute a javascript function on ASP.NET, but I've encountered an error that I can't seem to fix...</p> <p>I have alreay tried a small example that works... here it is...</p> <p>Aspx file</p> <pre><code>&lt;title&gt;Untitled Page&lt;/title&gt; &lt;script type="text/javascript" language="javascript"&gt; function ExecuteConfirm() { debugger var returnValue = confirm('Do you want to proceed further?'); if (returnValue) { document.getElementById('hdnExecuteAfterConfirm').value = "1"; document.getElementById('btnClickMe').click(); } } &lt;/script&gt; &lt;body&gt; &lt;form id="form1" runat="server"&gt; &lt;asp:Label runat="server" ID="lblMessage"&gt; &lt;/asp:Label&gt; &lt;div&gt; &lt;asp:Button ID="btnClickMe" runat="server" Text="Click me" onclick="btnClickMe_Click" /&gt; &lt;/div&gt; &lt;asp:HiddenField runat="server" ID="hdnExecuteAfterConfirm" /&gt; &lt;/form&gt; &lt;/body&gt; </code></pre> <p>CS file</p> <pre><code>protected void btnClickMe_Click(object sender, EventArgs e) { //Do server side processing before confirmation if (hdnExecuteAfterConfirm.Value != "1") { lblMessage.Text = "You clicked the button"; ClientScript.RegisterStartupScript(this.Page.GetType(), btnClickMe.ID, "ExecuteConfirm()", true); } //Do server side processing after confirmation else { //Proceed further with server side processing //Reset the value of hidden field hdnExecuteAfterConfirm.Value = ""; //Notify the user that processing is complete. ClientScript.RegisterStartupScript(this.Page.GetType(), btnClickMe.ID, "alert('Processing is complete.')", true); } } </code></pre> <p>The goal here is to display a confirm message the first time you click the button (if), and once you click YES on the confirm message it will repeat the button function, however, it'll do something different (else)...</p> <p>I'm trying to recreate this function on my project, but I am encountering an error...</p> <p>Here's what I have...</p> <p>Note, I'm not copying my entire project, those are just the parts that I had to change...</p> <p>Site.Master</p> <pre><code>&lt;script type="text/javascript" language="javascript"&gt; function ConfirmarRegistroFecha(strAdvertencia) { debugger var returnValue = strAdvertencia; if (returnValue) { try{ document.getElementById('hdnExecuteAfterConfirm').value = "1"; document.getElementById('btnGuardarEvento').click(); } catch(error){ alert(error); } } } &lt;/script&gt; </code></pre> <p>Agenda.aspx (I know that is to much, however, I'm copying it all, since maybe the error is around here somewhere. The point is that at least, inside is a HiddenField, and a button) </p> <pre><code>&lt;asp:View ID="ViewOperacionesAgenda2" runat="server"&gt; &lt;asp:HiddenField runat="server" ID="hdnExecuteAfterConfirm" /&gt; &lt;br /&gt; &lt;asp:Panel ID="pnlRegistrarEvento" runat="server" DefaultButton="btnGuardarEvento"&gt; &lt;table&gt; &lt;tr&gt; &lt;td align="left"&gt; Seleccione Vendedor: &lt;br /&gt; &lt;asp:DropDownList ID="dpdLstVendedoresAgenda" runat="server" Width="150px"&gt; &lt;/asp:DropDownList&gt; &lt;/td&gt; &lt;td align="left" rowspan="3"&gt; Descripcion: &lt;br /&gt; &lt;asp:TextBox ID="tbxAlAgendaDescripcion" runat="server" Height="150px" TextMode="MultiLine" ValidationGroup="gpAgendaAlta" Width="150px"&gt; &lt;/asp:TextBox&gt; &lt;/td&gt; &lt;td align="left" rowspan="3"&gt; Fecha: &lt;br /&gt; &lt;asp:Calendar ID="Calendar1" runat="server" BackColor="White" BorderColor="#3366CC" BorderWidth="1px" CellPadding="1" DayNameFormat="Shortest" Font-Names="Verdana" Font-Size="7pt" ForeColor="#003399" Height="150px" Width="150px"&gt; &lt;DayHeaderStyle BackColor="#99CCCC" ForeColor="#336666" Height="1px" /&gt; &lt;NextPrevStyle Font-Size="8pt" ForeColor="#CCCCFF" /&gt; &lt;OtherMonthDayStyle ForeColor="#999999" /&gt; &lt;SelectedDayStyle BackColor="#009999" Font-Bold="True" ForeColor="#CCFF99" /&gt; &lt;SelectorStyle BackColor="#99CCCC" ForeColor="#336666" /&gt; &lt;TitleStyle BackColor="#003399" BorderColor="#3366CC" BorderWidth="1px" Font-Bold="True" Font-Size="10pt" ForeColor="#CCCCFF" Height="25px" /&gt; &lt;TodayDayStyle BackColor="#99CCCC" ForeColor="White" /&gt; &lt;WeekendDayStyle BackColor="#CCCCFF" /&gt; &lt;/asp:Calendar&gt; &lt;/td&gt; &lt;td rowspan="3"&gt; &lt;table&gt; &lt;tr&gt; &lt;td align="left"&gt; Hora Inicio: &lt;br /&gt; &lt;asp:TextBox ID="tbxAlAgendaHoraInicio" runat="server" ValidationGroup="gpAgendaAlta" Width="130px"&gt;0:00 am&lt;/asp:TextBox&gt; &lt;br /&gt; &lt;asp:RegularExpressionValidator ID="RegularExpressionValidator3" runat="server" ControlToValidate="tbxAlAgendaHoraInicio" ErrorMessage="Hora Invalida: use 00:00 pm" ValidationExpression="^((0?[1-9]|1[012])(:[0-5]\d)((\ )?[ap](.)?m(.)?))" ValidationGroup="vgpRegistrarEvento" Font-Bold="True" ForeColor="Red"&gt; &lt;/asp:RegularExpressionValidator&gt; &lt;br /&gt; &lt;asp:RequiredFieldValidator ID="RequiredFieldValidator8" runat="server" ControlToValidate="tbxAlAgendaHoraInicio" ErrorMessage="Campo Requerido" ValidationGroup="vgpRegistrarEvento" Font-Bold="True" ForeColor="Red"&gt; &lt;/asp:RequiredFieldValidator&gt; &lt;/td&gt; &lt;/tr&gt; &lt;tr&gt; &lt;td align="left"&gt; Hora Final: &lt;br/&gt; &lt;asp:TextBox ID="tbxAlAgendaHoraFinal" runat="server" ValidationGroup="gpAgendaAlta" Width="130px"&gt;0:00 am&lt;/asp:TextBox&gt; &lt;br /&gt; &lt;asp:RegularExpressionValidator ID="RegularExpressionValidator4" runat="server" ControlToValidate="tbxAlAgendaHoraFinal" ErrorMessage="Hora Invalida: use 00:00 pm" ValidationExpression="^((0?[1-9]|1[012])(:[0-5]\d)((\ )?[ap](.)?m(.)?))" ValidationGroup="vgpRegistrarEvento" Font-Bold="True" ForeColor="Red"&gt; &lt;/asp:RegularExpressionValidator&gt; &lt;br /&gt; &lt;asp:RequiredFieldValidator ID="RequiredFieldValidator9" runat="server" ControlToValidate="tbxAlAgendaHoraFinal" ErrorMessage="Campo Requerido" ValidationGroup="vgpRegistrarEvento" Font-Bold="True" ForeColor="Red"&gt; &lt;/asp:RequiredFieldValidator&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; &lt;/td&gt; &lt;/tr&gt; &lt;tr&gt; &lt;td align="left"&gt; Seleccione Cliente: &lt;br /&gt; &lt;asp:DropDownList ID="dpdLstClientesAgenda" runat="server" AutoPostBack="True" onselectedindexchanged="dpdLstClientesAgenda_SelectedIndexChanged" Width="150px"&gt; &lt;/asp:DropDownList&gt; &lt;/td&gt; &lt;/tr&gt; &lt;tr&gt; &lt;td align="left"&gt; Tipo: &lt;br /&gt; &lt;asp:DropDownList ID="dpdLstAlAgendaTipo" runat="server" Width="150px"&gt; &lt;asp:ListItem&gt;Reunion&lt;/asp:ListItem&gt; &lt;asp:ListItem&gt;Entrevista&lt;/asp:ListItem&gt; &lt;asp:ListItem&gt;Venta&lt;/asp:ListItem&gt; &lt;asp:ListItem&gt;Soporte&lt;/asp:ListItem&gt; &lt;asp:ListItem&gt;Instalacion&lt;/asp:ListItem&gt; &lt;/asp:DropDownList&gt; &lt;/td&gt; &lt;/tr&gt; &lt;/table&gt; &lt;br /&gt; &lt;asp:Button ID="btnCancelarEvento" runat="server" CausesValidation="False" onclick="btnCancelarEvento_Click" Text="Cancelar" Width="90px" /&gt; &amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;asp:Button ID="btnGuardarEvento" runat="server" onclick="btnGuardarEvento_Click" Text="Guardar" ValidationGroup="vgpRegistrarEvento" Width="90px" /&gt; &lt;/asp:Panel&gt; </code></pre> <p></p> <p>Agenda.aspx.cs</p> <pre><code>protected void btnGuardarEvento_Click(object sender, EventArgs e) { if (hdnExecuteAfterConfirm.Value != "1") { strAdvertencia = "MESSAGE I WANT TO DISPLAY"; ClientScript.RegisterStartupScript(this.Page.GetType(), btnGuardarEvento.ID, "ConfirmarRegistroFecha(" + strAdvertencia + ")", true); } else { hdnExecuteAfterConfirm.Value = ""; //Rest of process } } </code></pre> <p>Using a debugger with Firebug, I can clearly see that on Site.Master, when it reaches..</p> <pre><code>document.getElementById('hdnExecuteAfterConfirm').value = "1"; </code></pre> <p>It displays the following exception:</p> <pre><code>TypeError: document.getElementById("hdnExecuteAfterConfirm") is null </code></pre> <p>I have already tried to copy the javascript on Agenda.aspx instead of Site.Master... and it still doesn't work...</p> <p>Does anyone know what the mistake here is... I'm new to javascript, so I'm still believing that is a syntax error...</p> <p>Thanks in advance and I hope you can help me</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USVictor
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POGetting Error On Javascript document.getElementById('name'). RETURNS NULL
      1. This table or related slice is empty.
      1. VTDownMod
    2. VO
      singulars
      1. POGetting Error On Javascript document.getElementById('name'). RETURNS NULL
      1. This table or related slice is empty.
      1. VTUpMod
    1. COCan you please create a minimal example that reproduces your problem?
      singulars
      1. POGetting Error On Javascript document.getElementById('name'). RETURNS NULL
      1. USmicha
    2. COVery big question!! Who can read that much???
      singulars
      1. POGetting Error On Javascript document.getElementById('name'). RETURNS NULL
      1. UShmmftg
    3. COare you sure that the element generated in JavaScript is not adorned with a master page prefix/suffix? ASP.NET had a way of creating rather verbose client ids - I'd say comment out your js and then inspect the DOM that ASPX generates.
      singulars
      1. POGetting Error On Javascript document.getElementById('name'). RETURNS NULL
      1. USJim O'Neil
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload