title: Check existing Data in Listview
body: <p>listview: <code>lvData</code></p>
  
  <pre><code>    acctcode     first      last
  
  1    DFNTN       High       Definition
  2    BLNCE       World      Balance 
  3    RNBOW       Rain       Bow
  </code></pre>
  
  <p>I want to add data in <code>lvData</code> using <code>textbox</code>. But first the program must check if the data provided in <code>textbox</code> already exists. Based on the <code>acctcode</code> column.</p>
  
  <p>here is my code:</p>
  
  <pre><code> Dim articlecheck As String = TEXTBOX.text
          Dim founditem As ListViewItem = LVDATA.FindItemWithText(articlecheck)
          If Not (founditem Is Nothing) Then
              MessageBox.Show("Data already exists!", "Duplicate", MessageBoxButtons.OK, MessageBoxIcon.Error)
              Exit Sub
          Else
            'ADD DATA in the LISTVIEW'
  </code></pre>
  
  <p>The problem is If I put value in textbox with something like this: <code>DFN</code>, <code>BLN</code>, <code>RNB</code>. My program will still show <code>"Data alrleady exist!"</code></p>