| CqlQueryExtensionsFirstOrDefaultTSource Method (TableTSource, ExpressionFuncTSource, Boolean) |
Returns a CqlQuery which after execution will return the first element of the sequence that satisfies a condition
or a default value if no such element is found.
To execute this CqlQuery use Execute() method.
Namespace: Cassandra.Data.Linq
Assembly: Cassandra (in Cassandra.dll) Version: 3.0.9 (git 5ca22bb)
SyntaxC#
public static CqlQuerySingleElement<TSource> FirstOrDefault<TSource>( this Table<TSource> source, Expression<Func<TSource, bool>> predicate )
Parameters
- source
- Type: Cassandra.Data.LinqTableTSource
The Table<TSource> to return the first element of. - predicate
- Type: System.Linq.ExpressionsExpressionFuncTSource, Boolean
A function to test each element for a condition.
Type Parameters
- TSource
- The type of the elements of source.
Return Value
Type: CqlQuerySingleElementTSourcea CqlQuery<TSource> which after execution will return default(TSource) if source is empty or if no element passes the test specified by predicate, otherwise the first element in source that passes the test specified by predicate.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type TableTSource. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).See Also