Recursive FindControl by Michael Palermo

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Added by Interface April 13, 2007

Need to find a control anywhere on the page or in a template? Here is the code to find it recursively. This example assumes the code is located in a custom base page.

<span style="color: teal;"> 1</span> <span style="color: blue;">public</span> T FindControl&lt;T&gt;(<span style="color: blue;">string</span> id) where T : Control
<span style="color: teal;"> 2</span> {
<span style="color: teal;"> 3</span>     <span style="color: blue;">return</span> FindControl&lt;T&gt;(Page, id);
<span style="color: teal;"> 4</span> }
<span style="color: teal;"> 5</span>
<span style="color: teal;"> 6</span> <span style="color: blue;">public</span> <span style="color: blue;">static</span> T FindControl&lt;T&gt;(Control startingControl, <span style="color: blue;">string</span> id) where T : Control
<span style="color: teal;"> 7</span> {
<span style="color: teal;"> 8</span>     <span style="color: green;">// this is null by default</span>
<span style="color: teal;"> 9</span>     T found = <span style="color: blue;">default</span>(T);
<span style="color: teal;"> 10</span>
<span style="color: teal;"> 11</span>     <span style="color: blue;">int</span> controlCount = startingControl.Controls.Count;
<span style="color: teal;"> 12</span>
<span style="color: teal;"> 13</span>     <span style="color: blue;">if</span> (controlCount &gt; <span style="color: maroon;">0</span>)
<span style="color: teal;"> 14</span>     {
<span style="color: teal;"> 15</span>         <span style="color: blue;">for</span> (<span style="color: blue;">int</span> i = <span style="color: maroon;">0</span>; i &lt; controlCount; i++)
<span style="color: teal;"> 16</span>         {
<span style="color: teal;"> 17</span>             Control activeControl = startingControl.Controls[i];
<span style="color: teal;"> 18</span>             <span style="color: blue;">if</span> (activeControl <span style="color: blue;">is</span> T)
<span style="color: teal;"> 19</span>             {
<span style="color: teal;"> 20</span>                 found = startingControl.Controls[i] <span style="color: blue;">as</span> T;
<span style="color: teal;"> 21</span>                 <span style="color: blue;">if</span> (<span style="color: blue;">string</span>.Compare(id, found.ID, <span style="color: maroon;">true</span>) == <span style="color: maroon;">0</span>) <span style="color: blue;">break</span>;
<span style="color: teal;"> 22</span>                 <span style="color: blue;">else</span> found = <span style="color: blue;">null</span>;
<span style="color: teal;"> 23</span>             }
<span style="color: teal;"> 24</span>             <span style="color: blue;">else</span>
<span style="color: teal;"> 25</span>             {
<span style="color: teal;"> 26</span>                 found = FindControl&lt;T&gt;(activeControl, id);
<span style="color: teal;"> 27</span>                 <span style="color: blue;">if</span> (found != <span style="color: blue;">null</span>) <span style="color: blue;">break</span>;
<span style="color: teal;"> 28</span>             }
<span style="color: teal;"> 29</span>         }
<span style="color: teal;"> 30</span>     }
<span style="color: teal;"> 31</span>     <span style="color: blue;">return</span> found;
<span style="color: teal;"> 32</span> }