GridView HyperLink field in C#

Use the DataNavigateUrlFields property, comma-delimited value with the fields for parameters in "KeywordSrchSumDtl.aspx?Keyword={0}&State={1}&City={2}"

<asp:HyperLinkField DataNavigateUrlFields="Keyword,State,City"
                    DataNavigateUrlFormatString="KeywordSrchSumDtl.aspx?Keyword={0}&State={1}&City={2}" 
                    Text="View Details" />

A couple of examples:

Passing two arguments in DataNavigateUrlFormatString in hyperlink field of .NET 2.0 Grid-View

Pass Multiple Values from a GridView to Another Page using ASP.NET

EDIT:

Set NavigateUrl of HyperLink in RowDataBound event of GridView

<asp:GridView ID="GridView1" runat="server" 
              AutoGenerateColumns="False" 
              DataKeyNames="Keyword"
              DataSourceID="SqlDataSource1" 
              onrowdatabound="GridView1_RowDataBound">
   <asp:TemplateField HeaderText="Keyword"  ItemStyle-HorizontalAlign="Center"          FooterStyle-HorizontalAlign="Center">
      <ItemTemplate>
          <asp:HyperLink ID="link" runat="server" Text='<%# Eval("Keyword") %>' />
      </ItemTemplate>
    </asp:TemplateField>
    .......
</asp:GridView>

Code behind:

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e) 
{ 
 if (e.Row.RowType == DataControlRowType.DataRow) 
 { 
    HyperLink hl = (HyperLink)e.Row.FindControl("link"); 
    if (hl != null) 
    { 
        DataRowView drv = (DataRowView)e.Row.DataItem; 
        string keyword = drv["Keyword"].ToString(); 
        string state = Request.QueryString["State"]; 
        string city = Request.QueryString["City"]; 
        hl.NavigateUrl = "~/KeywordSrchSumDtl.aspx?Keyword=" + keyword + "&State=" + Server.UrlEncode(state) + "&City=" + Server.UrlEncode(city); 
    } 
 } 
}