How to make a grdview field value a link -Anchor link

Question

Hi all.

 

DateTime dd = Convert.ToDateTime(site.Collection_Date);

dr["Collection Date"] = dd.ToShortDateString();

dr["Collection Time"] = site.Collection_Time;

dr["Collection Proof"] = "<a href=test.aspx>" + site.AttachImageReport + "</a>";

var st = db.tb_Status.FirstOrDefault(x => x.Status_Id == site.Vehicle_Status);

dr["Vehicle Status"] = st.Status;

 

I am using a gridview to display items like above. Now I can't make the field  dr["Collection Proof"] value to be a link.

 

Can you assist.