TypedTableBaseExtensions.ElementAtOrDefault<TRow>(TypedTableBase<TRow>, Int32) 方法
定义
返回序列中指定行处的元素;如果行超出范围,则返回默认值。Returns the element at a specified row in a sequence or a default value if the row is out of range.
public:
generic <typename TRow>
where TRow : System::Data::DataRow[System::Runtime::CompilerServices::Extension]
static TRow ElementAtOrDefault(System::Data::TypedTableBase<TRow> ^ source, int index);
public static TRow ElementAtOrDefault<TRow> (this System.Data.TypedTableBase<TRow> source, int index) where TRow : System.Data.DataRow;
public static TRow? ElementAtOrDefault<TRow> (this System.Data.TypedTableBase<TRow> source, int index) where TRow : System.Data.DataRow;
static member ElementAtOrDefault : System.Data.TypedTableBase<'Row (requires 'Row :> System.Data.DataRow)> * int -> 'Row (requires 'Row :> System.Data.DataRow)
<Extension()>
Public Function ElementAtOrDefault(Of TRow As DataRow) (source As TypedTableBase(Of TRow), index As Integer) As TRow
类型参数
- TRow
数组或行的类型。The type of the elements or the row.
参数
- source
- TypedTableBase<TRow>
要从中返回元素的可枚举对象。An enumerable object to return an element from.
- index
- Int32
要检索的从零开始的元素索引。The zero-based index of the element to retrieve.
返回
- TRow
序列中指定行处的元素。The element at a specified row in a sequence.