ASPX页面embed标签字符过多错误及Eval绑定写法咨询

Hey there, let's work through the two snags you're hitting with your ASPX TemplateField and embed tag:

1. Resolving the "Too many characters in character literal" error #

This error pops up because ASP.NET is misinterpreting your data binding expression when nested inside the src attribute's quotes. The fix boils down to two key adjustments:

• Properly nest your quotes (use single quotes for the src attribute so the double quotes in Eval() don't break parsing)
• URL-encode the file path to handle special characters (like spaces, &, or ?) that would break the Google Viewer URL structure.

2. Fixing embed functionality after closing the tag #

The embed tag is a self-closing HTML element, so it should end with />—this wasn't the cause of your broken functionality. The real issue was almost certainly the unencoded file path making Google Viewer unable to parse the URL correctly.

Correct Working Code #

Here's the adjusted template that fixes both problems:

<asp:TemplateField HeaderText="View files">
    <ItemTemplate>
        <embed 
            src='https://drive.google.com/viewerng/viewer?embedded=true&amp;url=<%# Server.UrlEncode(Eval("InvoiceFilePath").ToString()) %>'
            type="application/pdf"
            width="100%"
            height="600px"
            />
    </ItemTemplate>
</asp:TemplateField>

Key Notes to Keep in Mind: #

• Server.UrlEncode: This converts any special characters in your InvoiceFilePath to URL-safe formats, which Google Drive Viewer requires to load the file correctly.
• Absolute Path Validation: Make sure InvoiceFilePath stores a full, publicly accessible URL (e.g., https://your-server.com/invoices/inv123.pdf). If it's a relative path, use ResolveUrl() to convert it first:

  <%# Server.UrlEncode(ResolveUrl(Eval("InvoiceFilePath").ToString())) %>
  

• Self-closing Tag Compliance: The /> at the end of the embed tag is HTML-standard and won't interfere with functionality once the URL is properly formatted.

If you still run into issues, double-check that the InvoiceFilePath value is valid and that the file is publicly accessible (Google Viewer can't load files behind authentication walls).

内容的提问来源于stack exchange，提问作者atc