Get Selected Checkbox Value from Gridview in Asp.net C#

In this Blog as Work with in gridview Selected Checkbox ID Value can Get In C#.

ASPX Code:

  <div style="width: 104%; height: 243px; max-height: 243px; overflow: auto;">

   <asp:GridView ShowHeader="false" AutoGenerateColumns="false"                     ID="chklCategory" runat="server">

 <Columns>

                                                                                    <asp:TemplateField>

                                                                                        <ItemTemplate>

    <asp:CheckBox runat="server" AutoPostBack="true" ID="Checkbox_Category" Text='<%#bind("Name") %>' />

                                                                                              <asp:HiddenField runat="server" ID="hidCheck" Value='<%# bind("Id") %>' />

                                                                                       </ItemTemplate>

                                                                                        <ItemStyle HorizontalAlign="Left" />

                                </asp:TemplateField>

 </Columns>

 </asp:GridView>

C# Code:

The Gridview Selected Value can store Two ways. Store Database and Store data to String. 

In this Function can perform selected Value Can store the DataTable.

public DataTable DTCatIds()

        {

            //string str = "";

            DataTable dt = new DataTable();

            dt.Columns.Add("Id");

            foreach (GridViewRow row in chklCategory.Rows)

            {

                CheckBox Checkbox = (CheckBox)row.FindControl("Checkbox_Category");

                if (Checkbox.Checked)

                {

                    HiddenField hidCheck = (HiddenField)row.FindControl("hidCheck");

                    //str += hidCheck.Value + ",";

                    dt.Rows.Add(hidCheck.Value);

                    dt.NewRow();

                }

            }

            return dt;

            //return str;

        }

---------------------------------------------------------------

public String DTCatIds()

        {

            string str = "";

           

            foreach (GridViewRow row in chklCategory.Rows)

            {

                CheckBox Checkbox = (CheckBox)row.FindControl("Checkbox_Category");

                if (Checkbox.Checked)

                {

                    HiddenField hidCheck = (HiddenField)row.FindControl("hidCheck");

                    str += hidCheck.Value + ",";

                }

            }

            return str;

            

        }