# C1.C1Preview.Util.FastList.Add

## Content

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<h1 id="C1_C1Preview_Util_FastList_Add_" data-uid="C1.C1Preview.Util.FastList.Add*">Add Method
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<div class="markdown level0 summary"></div>
<div class="markdown level0 conceptual"></div>



<a id="C1_C1Preview_Util_FastList_Add_" data-uid="C1.C1Preview.Util.FastList.Add*"></a>
<h4 id="C1_C1Preview_Util_FastList_Add_System_IComparable_" data-uid="C1.C1Preview.Util.FastList.Add(System.IComparable)">Add(IComparable)</h4>
<div class="markdown level1 summary"><p>Adds an object implementing the <a class="xref" href="https://learn.microsoft.com/dotnet/api/system.icomparable">IComparable</a> interface to the current list.</p>
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<div class="markdown level1 conceptual"></div>
<h5 class="declaration">Declaration</h5>
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  <pre><code class="lang-csharp hljs">protected int Add(IComparable obj)</code></pre>
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  <pre><code class="lang-vbnet hljs">Protected Function Add(obj As IComparable) As Integer</code></pre>
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<h5 class="parameters">Parameters</h5>
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  <thead>
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      <th>Type</th>
      <th>Name</th>
      <th>Description</th>
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    <tr>
      <td><a class="xref" href="https://learn.microsoft.com/dotnet/api/system.icomparable">IComparable</a></td>
      <td><span class="parametername">obj</span></td>
      <td><p>The object to add (if the current list already contains this object, an exception is thrown).</p>
</td>
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  </tbody>
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<h5 class="returns">Returns</h5>
<table class="table table-bordered table-condensed">
  <thead>
    <tr>
      <th>Type</th>
      <th>Description</th>
    </tr>
  </thead>
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    <tr>
      <td><a class="xref" href="https://learn.microsoft.com/dotnet/api/system.int32">int</a></td>
      <td><p>The index of the added object in the current list.</p>
</td>
    </tr>
  </tbody>
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