正如我已经看见你前面的问题还，所以我建议你一件事，而不是保持你的GridView会话（这是昂贵的），可以使用 RowCommand 事件，后有按钮在这里，我不认为你需要复选框或 chk_CheckedChanged 时，您可以通过 PatientID 到下一个页面那里你可以编写查询所选行的数据插入到新表。

As i have seen your previous question also, So i can suggest you one thing, rather than keeping your gridview in session(which is expensive) you can use RowCommand event, and after having button here i don't think you need checkbox or chk_CheckedChanged event, you can pass the PatientID to your next page there you can write query to insert selected row data to your new table.

 <asp:TemplateField>
       <ItemTemplate>
        <asp:CheckBox runat="server" ID="chk" OnCheckedChanged="chk_CheckedChanged"  
         AutoPostBack="true" />
        <asp:Label runat="server" ID="lblPID" Visible="false" Text='<%# Eval("PatientId") %>'> 
       </asp:Label>
      <asp:Button ID="btnSelect" runat="server" Text="Select" CommandArgument='<%# 
       Eval("PatientId") %>' CommandName = "Select" />
      </ItemTemplate>
    </asp:TemplateField>



 protected void gvDoctorList_RowCommand(object sender, GridViewCommandEventArgs e)
        {
            if (e.CommandName == "select")
            {
                int pID = Convert.ToInt32(e.CommandArgument);
                // either put ID in session and check 
                Session["PatientID"] = Convert.ToString(pID);
                Server.Transfer("Patientstaticformatrix.aspx");
            }
        }

在Page_Load事件

On page_Load Event

 protected void Page_Load(object sender, EventArgs e)
    {
         string pID = Convert.ToString(Session["PatientID"]);
            if(!string.IsNullOrEmpty(pID))
            {
              int patientID = Convert.ToInt32(pID);
             //Call Stored procedure which will insert this record with this ID
             // to another table
            }    

    }