add ItemTemplate Manually to create Checkbox column in TemplateField

Question

I am creating the checkbox manually by adding templatefield and , but i cannot able to get the value of Checkbox Checked.

my code:

TemplateField tf = new  TemplateField();
tf.ItemTemplate = new clsMyTemplate();

CheckBox chkCheckBox1 = new CheckBox();
tf.ItemTemplate.InstantiateIn(chkCheckBox1);

chkCheckBox1.Checked =   
 (DataBinder.Eval(GrdDynamicControls.Rows[0].DataItem,strColumnName)
   .ToString().TrimStart().TrimEnd() == "True" ? true : false);

chkCheckBox1.CheckedChanged += new EventHandler(this.chkCheckBox1_CheckedChanged);

GrdDynamicControls.Columns.Add(tf);

public class clsMyTemplate : ITemplate
    {
        public void InstantiateIn(System.Web.UI.Control container)
        {


            CheckBox chkCheckBox1 = new CheckBox();

            container.Controls.Add(chkCheckBox1);

        }
    }

in this line it is showing me error:

chkCheckBox1.Checked = 
  (DataBinder.Eval(GrdDynamicControls.Rows[0].DataItem,strColumnName)
     .ToString().TrimStart().TrimEnd() == "True" ? true : false);

how to get the checked value bindind to it...

any idea???