18 lines
13 KiB
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18 lines
13 KiB
HTML
<html><head><meta http-equiv="X-UA-Compatible" content="IE=edge" /><link rel="shortcut icon" href="../icons/favicon.ico" /><style type="text/css">.OH_CodeSnippetContainerTabLeftActive, .OH_CodeSnippetContainerTabLeft,.OH_CodeSnippetContainerTabLeftDisabled { }.OH_CodeSnippetContainerTabRightActive, .OH_CodeSnippetContainerTabRight,.OH_CodeSnippetContainerTabRightDisabled { }.OH_footer { }</style><link rel="stylesheet" type="text/css" href="../styles/branding.css" /><link rel="stylesheet" type="text/css" href="../styles/branding-en-US.css" /><script type="text/javascript" src="../scripts/branding.js"> </script><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>DryadLinqQueryable.FirstAsQuery(TSource) Method (IQueryable(TSource), Expression(Func(TSource, Boolean)))</title><meta name="Language" content="en-us" /><meta name="Microsoft.Help.Id" content="M:Microsoft.Research.DryadLinq.DryadLinqQueryable.FirstAsQuery``1(System.Linq.IQueryable{``0},System.Linq.Expressions.Expression{System.Func{``0,System.Boolean}})" /><meta name="Description" content="Same as , but returns an <> containing a single element." /><meta name="Microsoft.Help.ContentType" content="Reference" /><meta name="BrandingAware" content="true" /><meta name="container" content="Microsoft.Research.DryadLinq" /><meta name="file" content="0b5ec7e8-a29f-e104-b8c6-56d15489af32" /><meta name="guid" content="0b5ec7e8-a29f-e104-b8c6-56d15489af32" /></head><body onload="OnLoad('cs')"><input type="hidden" id="userDataCache" class="userDataStyle" /><div class="OH_outerDiv"><div class="OH_outerContent"><table class="TitleTable"><tr><td class="OH_tdTitleColumn">DryadLinqQueryable<span id="LST7A0D1CD8_0"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_0?cpp=::|nu=.");</script>FirstAsQuery<span id="LST7A0D1CD8_1"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_1?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script><span class="typeparameter">TSource</span><span id="LST7A0D1CD8_2"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_2?cs=>|vb=)|cpp=>|fs=>|nu=)");</script> Method (IQueryable<span id="LST7A0D1CD8_3"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_3?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script><span class="typeparameter">TSource</span><span id="LST7A0D1CD8_4"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_4?cs=>|vb=)|cpp=>|fs=>|nu=)");</script>, Expression<span id="LST7A0D1CD8_5"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_5?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script>Func<span id="LST7A0D1CD8_6"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_6?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script><span class="typeparameter">TSource</span>, Boolean<span id="LST7A0D1CD8_7"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_7?cs=>|vb=)|cpp=>|fs=>|nu=)");</script><span id="LST7A0D1CD8_8"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_8?cs=>|vb=)|cpp=>|fs=>|nu=)");</script>)</td><td class="OH_tdRunningTitleColumn">DryadLINQ documentation</td></tr></table><div id="mainSection"><div id="mainBody"><span class="introStyle"></span><div class="summary">
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Same as <a href="http://msdn2.microsoft.com/en-us/library/bb535183" target="_blank">First<span id="LST7A0D1CD8_9"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_9?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script>TSource<span id="LST7A0D1CD8_10"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_10?cs=>|vb=)|cpp=>|fs=>|nu=)");</script>(IQueryable<span id="LST7A0D1CD8_11"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_11?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script>TSource<span id="LST7A0D1CD8_12"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_12?cs=>|vb=)|cpp=>|fs=>|nu=)");</script>, Expression<span id="LST7A0D1CD8_13"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_13?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script>Func<span id="LST7A0D1CD8_14"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_14?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script>TSource, Boolean<span id="LST7A0D1CD8_15"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_15?cs=>|vb=)|cpp=>|fs=>|nu=)");</script><span id="LST7A0D1CD8_16"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_16?cs=>|vb=)|cpp=>|fs=>|nu=)");</script>)</a>, but returns an <a href="http://msdn2.microsoft.com/en-us/library/bb495796" target="_blank">IQueryable</a><<span class="typeparameter">TSource</span>>
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containing a single element.
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</div><p> </p><strong>Namespace:</strong> <a href="efe6507e-9fd8-bbd3-8227-fd6ba9e289c1.htm">Microsoft.Research.DryadLinq</a><br /><strong>Assembly:</strong> Microsoft.Research.DryadLinq (in Microsoft.Research.DryadLinq.dll) Version: 0.2.1.0 (0.2.1.0)<div class="OH_CollapsibleAreaRegion"><div class="OH_regiontitle">Syntax</div><div class="OH_CollapsibleArea_HrDiv"><hr class="OH_CollapsibleArea_Hr" /></div></div><div class="OH_clear"> </div><div class="OH_CodeSnippetContainer"><div class="OH_CodeSnippetContainerTabs"><div class="OH_CodeSnippetContainerTabLeft" id="ID0ECCA_tabimgleft"> </div><div id="ID0ECCA_tab1" class="OH_CodeSnippetContainerTabFirst"><a href="#" onclick="javascript:ChangeTab('ID0ECCA','cs','1','3');return false;">C#</a></div><div id="ID0ECCA_tab2" class="OH_CodeSnippetContainerTab"><a href="#" onclick="javascript:ChangeTab('ID0ECCA','vb','2','3');return false;">VB</a></div><div id="ID0ECCA_tab3" class="OH_CodeSnippetContainerTab"><a href="#" onclick="javascript:ChangeTab('ID0ECCA','cpp','3','3');return false;">C++</a></div><div class="OH_CodeSnippetContainerTabRight" id="ID0ECCA_tabimgright"> </div></div><div class="OH_CodeSnippetContainerCodeCollection"><div class="OH_CodeSnippetToolBar"><div class="OH_CodeSnippetToolBarText"><a id="ID0ECCA_copyCode" href="#" onclick="javascript:CopyToClipboard('ID0ECCA');return false;" title="Copy">Copy</a></div></div><div id="ID0ECCA_code_Div1" class="OH_CodeSnippetContainerCode" style="display: block"><pre xml:space="preserve"><span class="keyword">public</span> <span class="keyword">static</span> <span class="identifier">IQueryable</span><TSource> <span class="identifier">FirstAsQuery</span><TSource>(
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<span class="keyword">this</span> <span class="identifier">IQueryable</span><TSource> <span class="parameter">source</span>,
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<span class="identifier">Expression</span><<span class="identifier">Func</span><TSource, <span class="identifier">bool</span>>> <span class="parameter">predicate</span>
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)
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</pre></div><div id="ID0ECCA_code_Div2" class="OH_CodeSnippetContainerCode" style="display: none"><pre xml:space="preserve"><<span class="identifier">ExtensionAttribute</span>>
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<span class="keyword">Public</span> <span class="keyword">Shared</span> <span class="keyword">Function</span> <span class="identifier">FirstAsQuery</span>(<span class="keyword">Of</span> TSource) (
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<span class="parameter">source</span> <span class="keyword">As</span> <span class="identifier">IQueryable</span>(<span class="keyword">Of</span> TSource),
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<span class="parameter">predicate</span> <span class="keyword">As</span> <span class="identifier">Expression</span>(<span class="keyword">Of</span> <span class="identifier">Func</span>(<span class="keyword">Of</span> TSource, <span class="identifier">Boolean</span>))
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) <span class="keyword">As</span> <span class="identifier">IQueryable</span>(<span class="keyword">Of</span> TSource)</pre></div><div id="ID0ECCA_code_Div3" class="OH_CodeSnippetContainerCode" style="display: none"><pre xml:space="preserve"><span class="keyword">public</span>:
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[<span class="identifier">ExtensionAttribute</span>]
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<span class="keyword">generic</span><<span class="keyword">typename</span> TSource>
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<span class="keyword">static</span> <span class="identifier">IQueryable</span><TSource>^ <span class="identifier">FirstAsQuery</span>(
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<span class="identifier">IQueryable</span><TSource>^ <span class="parameter">source</span>,
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<span class="identifier">Expression</span><<span class="identifier">Func</span><TSource, <span class="identifier">bool</span>>^>^ <span class="parameter">predicate</span>
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)</pre></div></div></div><script type="text/javascript">AddLanguageTabSet("ID0ECCA");</script><h4 class="subHeading">Parameters</h4><dl><dt><span class="parameter">source</span></dt><dd>Type: <a href="http://msdn2.microsoft.com/en-us/library/bb351562" target="_blank">System.Linq<span id="LST7A0D1CD8_17"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_17?cs=.|vb=.|cpp=::|nu=.|fs=.");</script>IQueryable</a><span id="LST7A0D1CD8_18"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_18?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script><span class="selflink"><span class="typeparameter">TSource</span></span><span id="LST7A0D1CD8_19"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_19?cs=>|vb=)|cpp=>|fs=>|nu=)");</script><br />The input sequence</dd><dt><span class="parameter">predicate</span></dt><dd>Type: <a href="http://msdn2.microsoft.com/en-us/library/bb335710" target="_blank">System.Linq.Expressions<span id="LST7A0D1CD8_20"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_20?cs=.|vb=.|cpp=::|nu=.|fs=.");</script>Expression</a><span id="LST7A0D1CD8_21"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_21?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script><a href="http://msdn2.microsoft.com/en-us/library/bb549151" target="_blank">Func</a><span id="LST7A0D1CD8_22"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_22?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script><span class="selflink"><span class="typeparameter">TSource</span></span>, <a href="http://msdn2.microsoft.com/en-us/library/a28wyd50" target="_blank">Boolean</a><span id="LST7A0D1CD8_23"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_23?cs=>|vb=)|cpp=>|fs=>|nu=)");</script><span id="LST7A0D1CD8_24"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_24?cs=>|vb=)|cpp=>|fs=>|nu=)");</script><br />A predicate to test each element for a condition</dd></dl><h4 class="subHeading">Type Parameters</h4><dl><dt><span class="parameter">TSource</span></dt><dd>The type of the elements of source</dd></dl><h4 class="subHeading">Return Value</h4>Type: <a href="http://msdn2.microsoft.com/en-us/library/bb351562" target="_blank">IQueryable</a><span id="LST7A0D1CD8_25"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_25?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script><span class="selflink"><span class="typeparameter">TSource</span></span><span id="LST7A0D1CD8_26"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_26?cs=>|vb=)|cpp=>|fs=>|nu=)");</script><br />The first element in the input sequence that satisfies the predicate<h4 class="subHeading">Usage Note</h4>In Visual Basic and C#, you can call this method as an instance method on any object of type <a href="http://msdn2.microsoft.com/en-us/library/bb351562" target="_blank">IQueryable</a><span id="LST7A0D1CD8_27"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_27?cs=<|vb=(Of |cpp=<|fs=<'|nu=(");</script><span class="selflink"><span class="typeparameter">TSource</span></span><span id="LST7A0D1CD8_28"></span><script type="text/javascript">AddLanguageSpecificTextSet("LST7A0D1CD8_28?cs=>|vb=)|cpp=>|fs=>|nu=)");</script>. When you use instance method syntax to call this method, omit the first parameter. For more information, see <a href="http://msdn.microsoft.com/en-us/library/bb384936.aspx" target="_blank">Extension Methods (Visual Basic)</a> or <a href="http://msdn.microsoft.com/en-us/library/bb383977.aspx" target="_blank">Extension Methods (C# Programming Guide)</a>.<div class="OH_CollapsibleAreaRegion"><div class="OH_regiontitle">Exceptions</div><div class="OH_CollapsibleArea_HrDiv"><hr class="OH_CollapsibleArea_Hr" /></div></div><div class="OH_clear"> </div><div class="tableSection"><table><tr><th class="ps_exceptionNameColumn">Exception</th><th class="ps_exceptionConditionColumn">Condition</th></tr><tr><td><a href="692e14c6-46ed-baaf-6b0f-b36cb74fe616.htm">DryadLinqException</a></td><td>No element in the input sequence satisfies the predicate</td></tr></table></div><div class="OH_CollapsibleAreaRegion" id="seeAlsoSection"><div class="OH_regiontitle">See Also</div><div class="OH_CollapsibleArea_HrDiv"><hr class="OH_CollapsibleArea_Hr" /></div></div><div class="OH_clear"> </div><h4 class="subHeading">Reference</h4><div class="seeAlsoStyle"><a href="6d67ec6b-96ed-0a8b-0ad4-1c0568c7bf91.htm">DryadLinqQueryable Class</a></div><div class="seeAlsoStyle"><a href="9af8461f-bf9b-b3fe-d9f0-0e03dffb3a85.htm">FirstAsQuery Overload</a></div><div class="seeAlsoStyle"><a href="efe6507e-9fd8-bbd3-8227-fd6ba9e289c1.htm">Microsoft.Research.DryadLinq Namespace</a></div></div></div></div></div><div id="OH_footer" class="OH_footer"> </div></body></html> |