my requirement is already selected subcategories will be checked and otheres are unchecked for user understanding
Check the sample and work accordingly.
foreach (DataListItem dli in DataList1.Items)
{
CheckBox ck = (CheckBox)dli.FindControl("ChkBox");
Label lbl = (Label)dli.FindControl("Label1");
{
if (ck.Text == ChildString)
{
ck.Checked = true;
}
else
{
}
}