title: Check only one checkbox at a time using checkboxlist
body: <hr>
  
  <p>i have a <code>dropdownlist</code> of <code>employees types</code> <code>( Project Manager, developer , qa</code> etc ). and a checkboxList of tasks that need to be assigned to each employee type.
   but for developer , there will be only one task at a time. i.e a person will be able to assign only one task to a developer at a time. if he selects a second one, the first choice  should be unchecked. for other employees with multiple tasks , its working fine. but how to put a check in developer case ?</p>
  
  <p>i have used below code but it is creating problem on edit , update. also when i select one task for a developer , all other checkbox get disabled and i cannot change the task.</p>
  
  <pre><code> If dt.Rows.Count &gt; 0 Then
          Dim developer As Boolean = Convert.ToBoolean(dt.Rows(0)(0).ToString())
          If developer Then
              For Each li As ListItem In cblTaskType.Items
                  If Not li.Value = employeeType Then
                      li.Selected = False
                      li.Enabled = False
                  End If
  
              Next
  </code></pre>