Question

I’ve one asp.net page and I want to load text into the textArea control which is in aspx page from into a variable in code behind (C#):

Code behind:

System.Web.UI.HtmlControls.HtmlTextArea Output1 = 
    (System.Web.UI.HtmlControls.HtmlTextArea)(FindControl("textarea1"));       
Output1.Value = Output.ToString();

ASP:

<div style ="width: 78%; float: right; height: 85px; display: block;" 
    class="message_text_box_left">

    <textarea id="textarea1" name="textarea1" cols="30" rows="3" 
        class="message_text_box" title="Share your Idias here..." 
        tabindex="1" onkeyup="addrow_fun();"></textarea>                        
</div>  

but it is giving error like

Object reference not set to an instance of an object.

Answer 1

You should add the

runat="server"

attribute to the text area.

Or, preferable you should use the TextBox ASP.NET control and set the TextMode property to TextBoxMode.MultiLine. Example follows:

Code behind:

Output1.Text = Output.ToString();

ASP:

<div style ="width: 78%; float: right; height: 85px; display: block;" 
    class="message_text_box_left">

    <asp:TextBox ID="Output1" Rows="3" 
        CssClass="message_text_box" ToolTip="Share your ideas here..." 
        TextMode="MultiLine" />                        
</div>