# C1.WPF.Maps.IMapVirtualSource.Request

## Content

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<h1 id="C1_WPF_Maps_IMapVirtualSource_Request_" data-uid="C1.WPF.Maps.IMapVirtualSource.Request*">Request Method
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<div class="markdown level0 summary"></div>
<div class="markdown level0 conceptual"></div>



<a id="C1_WPF_Maps_IMapVirtualSource_Request_" data-uid="C1.WPF.Maps.IMapVirtualSource.Request*"></a>
<h4 id="C1_WPF_Maps_IMapVirtualSource_Request_System_Double_System_Double_System_Windows_Point_System_Windows_Point_System_Action_System_Collections_ICollection__" data-uid="C1.WPF.Maps.IMapVirtualSource.Request(System.Double,System.Double,System.Windows.Point,System.Windows.Point,System.Action{System.Collections.ICollection})">Request(double, double, Point, Point, Action&lt;ICollection&gt;)</h4>
<div class="markdown level1 summary"><p>Called from <a class="xref" href="C1.WPF.Maps.MapVirtualLayer.html">MapVirtualLayer</a> when new items are needed for a map region.</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">void Request(double minZoom, double maxZoom, Point lowerLeft, Point upperRight, Action&lt;ICollection&gt; callback)</code></pre>
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  <pre><code class="lang-vbnet hljs">Sub Request(minZoom As Double, maxZoom As Double, lowerLeft As Point, upperRight As Point, callback As Action(Of ICollection))</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>
  </thead>
  <tbody>
    <tr>
      <td><a class="xref" href="https://learn.microsoft.com/dotnet/api/system.double">double</a></td>
      <td><span class="parametername">minZoom</span></td>
      <td><p>The minimum zoom of the region.</p>
</td>
    </tr>
    <tr>
      <td><a class="xref" href="https://learn.microsoft.com/dotnet/api/system.double">double</a></td>
      <td><span class="parametername">maxZoom</span></td>
      <td><p>The maximum zoom of the region.</p>
</td>
    </tr>
    <tr>
      <td><span class="xref">Point</span></td>
      <td><span class="parametername">lowerLeft</span></td>
      <td><p>The lower left coordinate of the region, in geographic coordinates.</p>
</td>
    </tr>
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      <td><span class="xref">Point</span></td>
      <td><span class="parametername">upperRight</span></td>
      <td><p>The upper right coordinate of the region, in geographic coordinates.</p>
</td>
    </tr>
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      <td><a class="xref" href="https://learn.microsoft.com/dotnet/api/system.action-1">Action</a>&lt;<a class="xref" href="https://learn.microsoft.com/dotnet/api/system.collections.icollection">ICollection</a>&gt;</td>
      <td><span class="parametername">callback</span></td>
      <td><p>A delegate to call with the elements inside the specified region.</p>
</td>
    </tr>
  </tbody>
</table>
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