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C# Default Expression
C# default expression is a class (DefaultExpression) that is used to represent default value of an empty expression. It is a sub class of System.Linq.Expressions.Expression namespace.
To get default value of an expression, Expression class provides a static method Default(Type) that returns instance of DefaultExpression class.
C# DefaultExpression class Syntax
It provides following properties and methods.
C# DefaultExpression Properties
| Name | Description |
|---|---|
| CanReduce | This property is inherited from Expressionn. It Indicates that the node can be reduced to a simpler node. |
| NodeType | It is used to return the node type of this expression. |
| Type | Gets the static type of the expression that this Expression represents. |
C# DefaultExpression Methods
| Name | Description |
|---|---|
| Accept(ExpressionVisitor) | It is used to dispatch the specific visit method for this node type. |
| Equals(Object) | It determines whether the specified object is equal to the current object or not. |
| GetHashCode() | This method serves as the default hash function. |
| GetType() | It is used to get the type of the current instance. |
| Reduce() | It is used to reduce this node to a simpler expression. |
| ReduceAndCheck() | It is used to reduce this node to a simpler expression by explicit checking. |
| ReduceExtensions() | It reduces the expression to a known node type. |
| ToString() | It is used to return a string representation of the Expression. |
| VisitChildren(ExpressionVisitor) | It reduces the node and then calls the visitor delegate on the reduced expression. |
The Expression.Default() method has the following signature.
It takes a parameter of System.Type type and returns an instance of DefaultExpression class.
C# Default Expression Example
Output:
Instace: default(Int32) Type: System.Int32 Can reduce: False Instance type: System.Linq.Expressions.DefaultExpression Node type: Default
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