Question

I have created one user control and need to convert that user control into custom control for the dll.

In that user control I need to use two javascripts also. Now could anyone help me to know how can I add that .js file reference into custom control code?

Usercontrol code:

<script src="Scripts/jquery-1.4.1.min.js" type="text/javascript"></script>
  <script src="Scripts/jquery.MultiFile.pack.js" type="text/javascript"></script>
    <div><%-- accept attribute can be used like accept="png|jpg"--%>
                    Multiple File Upload<br />
                    <asp:FileUpload ID="FileUpload10" runat="server" class="multi" accept="" />
                    <asp:Button ID="Button3" runat="server" Text="Submit" OnClick="jQueryUploadFiles" />

        <br />
        <asp:Label ID="lblMessage" runat="server" EnableViewState="false" ForeColor="Green" />
        <br />
        <asp:Label ID="lblError" runat="server" EnableViewState="false" ForeColor="Red" />
    </div>

usercontrol.ascx.cs

  private void FileUploadUsingJQuerySelectionMethod()
        {
            // check if file has been selected
            HttpFileCollection files = Request.Files;
            for (int i = 0; i < files.Count; i++)
            {
                HttpPostedFile file = files[i];
                if (file.ContentLength > 0)
                {
                    string path = ConfigurationManager.AppSettings["FilePath"];
                    string fileName = Path.GetFileName(file.FileName);

                    // now save the file to the disk
                    file.SaveAs(path + fileName);

                    lblMessage.Text += "File : <b>" + fileName + "</b> uploaded successfully !<br />";
                }
            }
        }

Answer 1

If I understand your question correctly, you want to make sure that wherever you use this user control, the necessary JS-files get loaded too?

I’d suggest having a look at the ClientDependency Framework for this.

From the description of the project:

The ClientDependency Framework is designed to affiliate any of your views & controls to CSS and JavaScript files without having to worry about if other views or controls have already been registered with them, making developing web components much easier because each component has it’s own dependencies registered for it to function.

If you find this framework to be a bit overkill, you could always use the scriptmanager control to include your js file in the containing page.
An explanation on how to do this can be found here:
http://www.infinitezest.com/articles/embedding-javascript-files-in-your-custom-controls.aspx