Artigo
11/18/2011

ConcurrencyCheckAttribute Class

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Designates that a property participates in optimistic concurrency checks.

Inheritance Hierarchy

System.Object
System.Attribute
System.ComponentModel.DataAnnotations.ConcurrencyCheckAttribute

Namespace: System.ComponentModel.DataAnnotations
Assembly: System.ComponentModel.DataAnnotations (in System.ComponentModel.DataAnnotations.dll)

Syntax

'Declaration
<AttributeUsageAttribute(AttributeTargets.Property Or AttributeTargets.Field, AllowMultiple := False,  _
    Inherited := True)> _
Public NotInheritable Class ConcurrencyCheckAttribute _
    Inherits Attribute

[AttributeUsageAttribute(AttributeTargets.Property|AttributeTargets.Field, AllowMultiple = false, 
    Inherited = true)]
public sealed class ConcurrencyCheckAttribute : Attribute

The ConcurrencyCheckAttribute type exposes the following members.

Constructors

	Name	Description
	ConcurrencyCheckAttribute	Initializes a new instance of the ConcurrencyCheckAttribute class.

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Methods

	Name	Description
	Equals	Infrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
	GetHashCode	Returns the hash code for this instance. (Inherited from Attribute.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	Match	When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)

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Remarks

You apply the ConcurrencyCheckAttribute attribute to a property to specify that the property serves as an indicator of whether the data record in the Silverlight application is still current with the data record in the data source. The value of the property should be compared to the value of the property in the data source before updating the data record. If the values are not equal, the data record in the data source has been changed by another process and the update should not overwrite the changed values.

Version Information

Silverlight

Supported in: 5, 4, 3

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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