How to use NavigateURL for HyperLink to transfer data to another page using C# and VB.Net in ASP.Net

I have a web page that has this code below.

When I click on the link, the details page doesn't display any detail information of that particular record. I tried different ways but it's still not working yet.

The data of my company name is something like this:  

Company A - 12

Company B

Company C 12-33

The code for hyperlink is below. If I replace the CompanyName with companyID then the detailed page works perfect. It just doesn't work when I replace CompanyID with CompanyName.

<asp:TemplateField>
     <ItemTemplate>
           <asp:HyperLink ID="Details1" Text="Details" runat="server"
           NavigateUrl='<%# Eval("CompanyName", "~/CustomerDetails.aspx?CompanyName=" + Server.UrlEncode(Eval("CompanyName").ToString())) %>' />
     </ItemTemplate>
</asp:TemplateField>

The URL string that is displayed on the URL block is:

http://companyname/CustomerDetails.aspx?CompanyName=xxx yy 12-2

What am I missing here?

Thanks so much.