DbExpressionBuilder.Project(DbExpressionBinding, DbExpression) 方法

定义

创建一个新的 DbProjectExpression,它对给定的输入集投影指定的表达式。Creates a new DbProjectExpression that projects the specified expression over the given input set.

public:
[System::Runtime::CompilerServices::Extension]
 static System::Data::Common::CommandTrees::DbProjectExpression ^ Project(System::Data::Common::CommandTrees::DbExpressionBinding ^ input, System::Data::Common::CommandTrees::DbExpression ^ projection);
public static System.Data.Common.CommandTrees.DbProjectExpression Project (this System.Data.Common.CommandTrees.DbExpressionBinding input, System.Data.Common.CommandTrees.DbExpression projection);
static member Project : System.Data.Common.CommandTrees.DbExpressionBinding * System.Data.Common.CommandTrees.DbExpression -> System.Data.Common.CommandTrees.DbProjectExpression
<Extension()>
Public Function Project (input As DbExpressionBinding, projection As DbExpression) As DbProjectExpression

参数

input
DbExpressionBinding

一个指定输入集的表达式绑定。An expression binding that specifies the input set.

projection
DbExpression

要对集投影的表达式。An expression to project over the set.

返回

DbProjectExpression

表示投影运算的新 DbProjectExpression。A new DbProjectExpression that represents the projection operation.

例外

inputprojection 为 null。input or projection is null.

适用于