# C1.Web.Mvc.ComboBoxBase-1

## Content

<div class="doc-site-dotnet-api-container">



  <h1 id="C1_Web_Mvc_ComboBoxBase_1" data-uid="C1.Web.Mvc.ComboBoxBase`1" class="text-break">ComboBoxBase&lt;T&gt; Class
</h1>
  <div class="markdown level0 summary"><p>The ComboBox control allows users to pick strings from lists. The control automatically completes entries as the user types, and allows users to show a drop-down list with the items available.</p>
</div>
  <div class="markdown level0 conceptual"></div>
  <div class="inheritance">
    <h5>Inheritance</h5>
    <div class="level0"><a class="xref" href="https://learn.microsoft.com/dotnet/api/system.object">object</a></div>
    <div class="level1"><a class="xref" href="C1.Web.Mvc.Component.html">Component</a></div>
    <div class="level2"><a class="xref" href="C1.Web.Mvc.Control.html">Control</a></div>
    <div class="level3"><a class="xref" href="C1.Web.Mvc.ItemsBoundControl-1.html">ItemsBoundControl</a>&lt;T&gt;</div>
    <div class="level4"><a class="xref" href="C1.Web.Mvc.DropDown-1.html">DropDown</a>&lt;T&gt;</div>
    <div class="level5"><span class="xref">ComboBoxBase&lt;T&gt;</span></div>
      <div class="level6"><a class="xref" href="C1.Web.Mvc.AutoCompleteBase-1.html">AutoCompleteBase&lt;T&gt;</a></div>
      <div class="level6"><a class="xref" href="C1.Web.Mvc.ComboBox-1.html">ComboBox&lt;T&gt;</a></div>
      <div class="level6"><a class="xref" href="C1.Web.Mvc.InputTime-1.html">InputTime&lt;T&gt;</a></div>
      <div class="level6"><a class="xref" href="C1.Web.Mvc.MenuBase-1.html">MenuBase&lt;T&gt;</a></div>
      <div class="level6"><a class="xref" href="C1.Web.Mvc.MultiSelect-1.html">MultiSelect&lt;T&gt;</a></div>
  </div>
  <div class="implements">
    <h5>Implements</h5>
    <div><a class="xref" href="https://learn.microsoft.com/dotnet/api/microsoft.aspnetcore.html.ihtmlcontent">IHtmlContent</a></div>
    <div><a class="xref" href="C1.Web.Mvc.ITemplate.html">ITemplate</a></div>
    <div><a class="xref" href="C1.Web.Mvc.IDropDown.html">IDropDown</a></div>
  </div>
  <h6><strong>Namespace</strong>: <a class="xref" href="C1.Web.Mvc.html">C1.Web.Mvc</a></h6>
  <h6><strong>Assembly</strong>: C1.AspNetCore.Mvc.dll</h6>
  <h5 id="C1_Web_Mvc_ComboBoxBase_1_syntax">Syntax</h5>
  <div class="codewrapper">
    <pre><code class="lang-csharp hljs">public abstract class ComboBoxBase&lt;T&gt; : DropDown&lt;T&gt;, IHtmlContent, ITemplate, IDropDown</code></pre>
  </div>
  <div class="codewrapper">
    <pre><code class="lang-vbnet hljs">Public MustInherit Class ComboBoxBase(Of T)
    Inherits DropDown(Of T)
    Implements IHtmlContent, ITemplate, IDropDown</code></pre>
  </div>
  <h5 class="typeParameters">Type Parameters</h5>
  <table class="table table-bordered table-condensed">
    <thead>
      <tr>
        <th>Name</th>
        <th>Description</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td><span class="parametername">T</span></td>
        <td></td>
      </tr>
    </tbody>
  </table>
  <h3 id="constructors">Constructors
</h3>
  <table class="table table-bordered table-condensed">
    <thead>
      <tr>
        <th>Name</th>
        <th>Description</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1__ctor_Microsoft_AspNetCore_Mvc_Rendering_IHtmlHelper_System_String_" data-uid="C1.Web.Mvc.ComboBoxBase`1.#ctor(Microsoft.AspNetCore.Mvc.Rendering.IHtmlHelper,System.String)">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.-ctor.html#C1_Web_Mvc_ComboBoxBase_1__ctor_Microsoft_AspNetCore_Mvc_Rendering_IHtmlHelper_System_String_">ComboBoxBase(IHtmlHelper, string)</a>
        </td>
        <td class="markdown level1 summary"><p>Creates one <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.html">ComboBoxBase&lt;T&gt;</a> instance.</p>
</td>
      </tr>
    </tbody>
  </table>
  <h3 id="properties">Properties
</h3>
  <table class="table table-bordered table-condensed">
    <thead>
      <tr>
        <th>Name</th>
        <th>Description</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_AriaLabelledBy" data-uid="C1.Web.Mvc.ComboBoxBase`1.AriaLabelledBy">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.AriaLabelledBy.html#C1_Web_Mvc_ComboBoxBase_1_AriaLabelledBy">AriaLabelledBy</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the aria-labelledby attribute of input element.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_CaseSensitiveSearch" data-uid="C1.Web.Mvc.ComboBoxBase`1.CaseSensitiveSearch">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.CaseSensitiveSearch.html#C1_Web_Mvc_ComboBoxBase_1_CaseSensitiveSearch">CaseSensitiveSearch</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets a value that determines whether searches performed while the user types should case-sensitive.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_DisplayMemberPath" data-uid="C1.Web.Mvc.ComboBoxBase`1.DisplayMemberPath">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.DisplayMemberPath.html#C1_Web_Mvc_ComboBoxBase_1_DisplayMemberPath">DisplayMemberPath</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the name of the property to use as the visual representation of the items.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_HandleWheel" data-uid="C1.Web.Mvc.ComboBoxBase`1.HandleWheel">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.HandleWheel.html#C1_Web_Mvc_ComboBoxBase_1_HandleWheel">HandleWheel</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets a value that determines whether the user can use the mouse wheel to change the currently selected item.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_HeaderPath" data-uid="C1.Web.Mvc.ComboBoxBase`1.HeaderPath">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.HeaderPath.html#C1_Web_Mvc_ComboBoxBase_1_HeaderPath">HeaderPath</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the name of a property to use for getting the value displayed in the control's input element.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_IsContentHtml" data-uid="C1.Web.Mvc.ComboBoxBase`1.IsContentHtml">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.IsContentHtml.html#C1_Web_Mvc_ComboBoxBase_1_IsContentHtml">IsContentHtml</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets a value indicating whether the drop-down list displays items as plain text or as HTML.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_IsEditable" data-uid="C1.Web.Mvc.ComboBoxBase`1.IsEditable">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.IsEditable.html#C1_Web_Mvc_ComboBoxBase_1_IsEditable">IsEditable</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets a value that enables or disables editing of the text in the input element of the ComboBox (defaults to false).</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_IsRequired" data-uid="C1.Web.Mvc.ComboBoxBase`1.IsRequired">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.IsRequired.html#C1_Web_Mvc_ComboBoxBase_1_IsRequired">IsRequired</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets a value that determines whether the control value must be set to a non-null value or whether it can be set to null (by deleting the content of the control).</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_ItemFormatter" data-uid="C1.Web.Mvc.ComboBoxBase`1.ItemFormatter">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.ItemFormatter.html#C1_Web_Mvc_ComboBoxBase_1_ItemFormatter">ItemFormatter</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets a function used to customize the values shown in the drop-down list.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_ItemTemplateContent" data-uid="C1.Web.Mvc.ComboBoxBase`1.ItemTemplateContent">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.ItemTemplateContent.html#C1_Web_Mvc_ComboBoxBase_1_ItemTemplateContent">ItemTemplateContent</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the content of the template used to generate each list item.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_ItemTemplateId" data-uid="C1.Web.Mvc.ComboBoxBase`1.ItemTemplateId">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.ItemTemplateId.html#C1_Web_Mvc_ComboBoxBase_1_ItemTemplateId">ItemTemplateId</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the id of the template used to generate each list item.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_KeyActionDownArrow" data-uid="C1.Web.Mvc.ComboBoxBase`1.KeyActionDownArrow">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.KeyActionDownArrow.html#C1_Web_Mvc_ComboBoxBase_1_KeyActionDownArrow">KeyActionDownArrow</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the action to perform when the DOWN ARROW key is pressed.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_KeyActionPrintCharacters" data-uid="C1.Web.Mvc.ComboBoxBase`1.KeyActionPrintCharacters">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.KeyActionPrintCharacters.html#C1_Web_Mvc_ComboBoxBase_1_KeyActionPrintCharacters">KeyActionPrintCharacters</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the action to perform when printable character keys are pressed (letters, numbers, symbols).</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_KeyActionTab" data-uid="C1.Web.Mvc.ComboBoxBase`1.KeyActionTab">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.KeyActionTab.html#C1_Web_Mvc_ComboBoxBase_1_KeyActionTab">KeyActionTab</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the action to perform when the TAB key is pressed.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_KeyActionUpArrow" data-uid="C1.Web.Mvc.ComboBoxBase`1.KeyActionUpArrow">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.KeyActionUpArrow.html#C1_Web_Mvc_ComboBoxBase_1_KeyActionUpArrow">KeyActionUpArrow</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the action to perform when the UP ARROW key is pressed.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_MaxDropDownHeight" data-uid="C1.Web.Mvc.ComboBoxBase`1.MaxDropDownHeight">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.MaxDropDownHeight.html#C1_Web_Mvc_ComboBoxBase_1_MaxDropDownHeight">MaxDropDownHeight</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the maximum height of the drop-down list.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_MaxDropDownWidth" data-uid="C1.Web.Mvc.ComboBoxBase`1.MaxDropDownWidth">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.MaxDropDownWidth.html#C1_Web_Mvc_ComboBoxBase_1_MaxDropDownWidth">MaxDropDownWidth</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the maximum width of the drop-down list.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_OnClientFormatItem" data-uid="C1.Web.Mvc.ComboBoxBase`1.OnClientFormatItem">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.OnClientFormatItem.html#C1_Web_Mvc_ComboBoxBase_1_OnClientFormatItem">OnClientFormatItem</a>
        </td>
        <td class="markdown level1 summary"><p>Event that fires when items in the drop-down list are created.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_OnClientItemsSourceChanged" data-uid="C1.Web.Mvc.ComboBoxBase`1.OnClientItemsSourceChanged">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.OnClientItemsSourceChanged.html#C1_Web_Mvc_ComboBoxBase_1_OnClientItemsSourceChanged">OnClientItemsSourceChanged</a>
        </td>
        <td class="markdown level1 summary"><p>Occurs when the value of the itemsSource property changes.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_OnClientSelectedIndexChanged" data-uid="C1.Web.Mvc.ComboBoxBase`1.OnClientSelectedIndexChanged">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.OnClientSelectedIndexChanged.html#C1_Web_Mvc_ComboBoxBase_1_OnClientSelectedIndexChanged">OnClientSelectedIndexChanged</a>
        </td>
        <td class="markdown level1 summary"><p>Occurs when the value of the SelectedIndex property changes.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_SelectedIndex" data-uid="C1.Web.Mvc.ComboBoxBase`1.SelectedIndex">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.SelectedIndex.html#C1_Web_Mvc_ComboBoxBase_1_SelectedIndex">SelectedIndex</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the index of the currently selected item in the drop-down list.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_SelectedItem" data-uid="C1.Web.Mvc.ComboBoxBase`1.SelectedItem">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.SelectedItem.html#C1_Web_Mvc_ComboBoxBase_1_SelectedItem">SelectedItem</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the item that is currently selected in the drop-down list.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_SelectedValue" data-uid="C1.Web.Mvc.ComboBoxBase`1.SelectedValue">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.SelectedValue.html#C1_Web_Mvc_ComboBoxBase_1_SelectedValue">SelectedValue</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the value of the SelectedValue, obtained using the SelectedValuePath.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_SelectedValuePath" data-uid="C1.Web.Mvc.ComboBoxBase`1.SelectedValuePath">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.SelectedValuePath.html#C1_Web_Mvc_ComboBoxBase_1_SelectedValuePath">SelectedValuePath</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the name of the property used to get the SelectedValue from the SelectedItem.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_ShowGroups" data-uid="C1.Web.Mvc.ComboBoxBase`1.ShowGroups">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.ShowGroups.html#C1_Web_Mvc_ComboBoxBase_1_ShowGroups">ShowGroups</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets a value that determines whether the drop-down should include group header items to delimit data groups.</p>
</td>
      </tr>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_VirtualizationThreshold" data-uid="C1.Web.Mvc.ComboBoxBase`1.VirtualizationThreshold">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.VirtualizationThreshold.html#C1_Web_Mvc_ComboBoxBase_1_VirtualizationThreshold">VirtualizationThreshold</a>
        </td>
        <td class="markdown level1 summary"><p>Gets or sets the minimum number of rows and/or columns required to enable virtualization in the ComboBox</p>
</td>
      </tr>
    </tbody>
  </table>
  <h3 id="methods">Methods
</h3>
  <table class="table table-bordered table-condensed">
    <thead>
      <tr>
        <th>Name</th>
        <th>Description</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td id="C1_Web_Mvc_ComboBoxBase_1_Render_System_IO_TextWriter_System_Text_Encodings_Web_HtmlEncoder_" data-uid="C1.Web.Mvc.ComboBoxBase`1.Render(System.IO.TextWriter,System.Text.Encodings.Web.HtmlEncoder)">
          <a class="xref" href="C1.Web.Mvc.ComboBoxBase-1.Render.html#C1_Web_Mvc_ComboBoxBase_1_Render_System_IO_TextWriter_System_Text_Encodings_Web_HtmlEncoder_">Render(TextWriter, HtmlEncoder)</a>
        </td>
        <td class="markdown level1 summary"></td>
      </tr>
    </tbody>
  </table>

</div>
