# C1.Win.TreeView.C1TreeView.OnCheckStateChanging

## Content

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<h1 id="C1_Win_TreeView_C1TreeView_OnCheckStateChanging_" data-uid="C1.Win.TreeView.C1TreeView.OnCheckStateChanging*">OnCheckStateChanging Method
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<div class="markdown level0 conceptual"></div>



<a id="C1_Win_TreeView_C1TreeView_OnCheckStateChanging_" data-uid="C1.Win.TreeView.C1TreeView.OnCheckStateChanging*"></a>
<h4 id="C1_Win_TreeView_C1TreeView_OnCheckStateChanging_C1_Win_TreeView_C1TreeViewCancelEventArgs_" data-uid="C1.Win.TreeView.C1TreeView.OnCheckStateChanging(C1.Win.TreeView.C1TreeViewCancelEventArgs)">OnCheckStateChanging(C1TreeViewCancelEventArgs)</h4>
<div class="markdown level1 summary"><p>Fires the <a class="xref" href="C1.Win.TreeView.C1TreeView.CheckStateChanging.html">CheckStateChanging</a> event.</p>
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<h5 class="declaration">Declaration</h5>
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  <pre><code class="lang-csharp hljs">protected virtual void OnCheckStateChanging(C1TreeViewCancelEventArgs e)</code></pre>
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  <pre><code class="lang-vbnet hljs">Protected Overridable Sub OnCheckStateChanging(e As C1TreeViewCancelEventArgs)</code></pre>
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<h5 class="parameters">Parameters</h5>
<table class="table table-bordered table-condensed">
  <thead>
    <tr>
      <th>Type</th>
      <th>Name</th>
      <th>Description</th>
    </tr>
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  <tbody>
    <tr>
      <td><a class="xref" href="C1.Win.TreeView.C1TreeViewCancelEventArgs.html">C1TreeViewCancelEventArgs</a></td>
      <td><span class="parametername">e</span></td>
      <td></td>
    </tr>
  </tbody>
</table>
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