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protected void btnUpdate_Click(object sender, EventArgs e)
        {
            char gen;

            #region feed Value

            _objEntityStudent.FirstName = txtFirstName.Text.ToString().Trim().Replace("'", "");
            _objEntityStudent.LastName = txtLastName.Text.ToString().Trim().Replace("'", "");
            if (rbGenderFemale.Checked)
            {
                gen = 'F';
            }
            else
            {
                gen = 'M';
            }
            _objEntityStudent.Gender = gen;
            _objEntityStudent.Email = txtEmail.Text.ToString().Trim().Replace("'", "");
            _objEntityStudent.Phone = txtPhone.Text.ToString().Trim().Replace("'", "");
            _objEntityStudent.Mobile = txtMobile.Text.ToString().Trim().Replace("'", "");
            _objEntityStudent.Address = txtAddress.Text.ToString().Trim().Replace("'", "");
            try
            {
                _objEntityStudent.DOB = Convert.ToDateTime(txtDOB.Text.ToString().Trim().Replace("'", ""));
            }
            catch (Exception ex)
            {
                lblError.Text = "Start Date not in proper format !";
                return;
            }
            _objEntityStudent.BloodGroup = txtBloodGroup.Text.ToString().Trim().Replace("'", "");
            try
            {
                _objEntityStudent.AdmissionDate = Convert.ToDateTime(txtAdmissionDate.Text.ToString().Trim().Replace("'", ""));
            }
            catch (Exception ex)
            {
                lblError.Text = "Admission Date not in proper format !";
                return;
            }

            _objEntityStudent.CityId = Convert.ToInt32(ddlCity.SelectedValue);
            _objEntityStudent.StateId = Convert.ToInt32(ddlState.SelectedValue);
            _objEntityStudent.Pincode = txtPincode.Text.ToString().Trim().Replace("'", "");

            _objEntityStudent.Theme = ddlTheme.SelectedValue;
            _objEntityStudent.Menu = ddlMenu.SelectedValue;

            _objEntityStudent.Description = txtDescription.Text.ToString().Trim().Replace("'", "");
            _objEntityStudent.InstituteName = txtInstituteName.Text.ToString().Trim().Replace("'", "");
            _objEntityStudent.ClassName = txtClassName.Text.ToString().Trim().Replace("'", "");
            _objEntityStudent.YearPassing = ddlYearPassing.SelectedItem.Text.ToString().Trim().Replace("'", "");
            _objEntityStudent.ObtainedMarks = txtObtaineMarks.Text.ToString().Trim().Replace("'", "");
            _objEntityStudent.IsActive = Convert.ToInt32(ddlActive.SelectedValue);

            _objEntityStudent.UpdatedBy = 0;
            _objEntityStudent.DeletedBy = 0;
            _objEntityStudent.IsDeleted = 0;
            #endregion

            _objEntityStudent.Mode = Mode.Update;
            _objEntityStudent.FirstName = this.txtFirstName.Text;
            _objEntityStudent.LastName = this.txtLastName.Text;
            _objEntityStudent.StudentId = Convert.ToInt32(Session["LoginId"].ToString());
            _objEntityStudent.CustomerId = Convert.ToInt32(Session["CustomerId"].ToString());
            _objEntityStudent.UpdatedBy = Convert.ToInt32(Session["CustomerId"].ToString());
            // StudentId = 2;
            StudentId = _objIBALStudent.UpdateStudent(_objEntityStudent);

            if (StudentId == 0)
            {
                lblError.ForeColor = Color.Red;
                lblError.Text = "<img src='images/alert.png' alt='' /> Error in Student data updation";
            }
            else
            {
                if (_strError.Length == 0)
                {
                    ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "Close_Window", "alert('Student Updated Successfully !'); document.location.href='SelfProfile.aspx'; ", true);
                }
                else
                {
                    ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "Close_Window", "alert('" + _strError + "'); ", true);
                }
            }

            pnlEdit.Visible = false; pnlView.Visible = true;
        }
    }
}

//In BAL
   #region UpdateStudent
        public Int64 UpdateStudent(EntityStudent objEntityStudent)
        {
            return _objDalSqlServer.UpdateStudent(objEntityStudent);
        }
        #endregion

//In DAL
 #region Update Student Batch Detail
                Int32 StudentId = Convert.ToInt32(_objSqlParameter[33].Value.ToString());
               string[] arrayBatchIds = objEntityStudent.BatchIds.Split(',');
                string strSql = "";                
strSql = " Delete StudentBatchMapping Where CustomerId=" + objEntityStudent.CustomerId;
                strSql += "  and StudentId=" + objEntityStudent.StudentId;
                SqlHelper.ExecuteNonQuery(_objSqlConnection, CommandType.Text, strSql);

                for (int i = 0; i < arrayBatchIds.Length; i++)
                {
                    strSql = " Insert Into StudentBatchMapping (CustomerId,StudentId,BatchId) Values (";
                    strSql += objEntityStudent.CustomerId + "," + objEntityStudent.StudentId + "," + arrayBatchIds[i].ToString() + ")";
                    SqlHelper.ExecuteNonQuery(_objSqlConnection, CommandType.Text, strSql);
                }
                #endregion

                return StudentId;
            }
            catch (Exception ex)
            {
                //System.Diagnostics.Trace.TraceError("Error : Company Name - {0} :: DalSqlAzure : UpdateUser : {1} ", HttpContext.Current.Session["CompanyName"].ToString(), ex.Message);
                return 0;
            }
            finally
            {
                _objSqlConnection.Close();
                _objSqlConnection.Dispose();
            }
        }
        #endregion