DisplayFormatAttribute Class
 

Specifies how data fields are displayed and formatted by ASP.NET Dynamic Data.

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

SystemObject
   SystemAttribute
    System.ComponentModel.DataAnnotationsDisplayFormatAttribute

[AttributeUsageAttribute(AttributeTargets.Property | AttributeTargets.Field, 
	AllowMultiple = false)]
public class DisplayFormatAttribute : Attribute
[AttributeUsageAttribute(AttributeTargets::Property | AttributeTargets::Field, 
	AllowMultiple = false)]
public ref class DisplayFormatAttribute : Attribute
[<AttributeUsageAttribute(AttributeTargets.Property | AttributeTargets.Field,
    AllowMultiple = false)>]
type DisplayFormatAttribute = 
    class
        inherit Attribute
    end
<AttributeUsageAttribute(AttributeTargets.Property Or AttributeTargets.Field,
	AllowMultiple := False)>
Public Class DisplayFormatAttribute
	Inherits Attribute
NameDescription
System_CAPS_pubmethod DisplayFormatAttribute

Initializes a new instance of the DisplayFormatAttribute class.

NameDescription
System_CAPS_pubproperty

Gets or sets a value that indicates whether the formatting string that is specified by the property is applied to the field value when the data field is in edit mode.

System_CAPS_pubproperty

Gets or sets a value that indicates whether empty string values ("") are automatically converted to null when the data field is updated in the data source.

System_CAPS_pubproperty

Gets or sets the display format for the field value.

System_CAPS_pubproperty

Gets or sets a value that indicates whether the field should be HTML-encoded.

System_CAPS_pubproperty

Gets or sets the text that is displayed for a field when the field's value is null.

System_CAPS_pubproperty

When implemented in a derived class, gets a unique identifier for this Attribute.(Inherited from Attribute.)

NameDescription
System_CAPS_pubmethod Equals

This API supports the product infrastructure and is not intended to be used directly from your code. Returns a value that indicates whether this instance is equal to a specified object.(Inherited from Attribute.)

System_CAPS_protmethod Finalize

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethod GetHashCode

Returns the hash code for this instance.(Inherited from Attribute.)

System_CAPS_pubmethod GetType

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethod IsDefaultAttribute

When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.(Inherited from Attribute.)

System_CAPS_pubmethod Match

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.(Inherited from Attribute.)

System_CAPS_protmethod MemberwiseClone

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethod ToString

Returns a string that represents the current object.(Inherited from Object.)

NameDescription
System_CAPS_pubinterface System_CAPS_privmethod _AttributeGetIDsOfNames

Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from Attribute.)

System_CAPS_pubinterface System_CAPS_privmethod _AttributeGetTypeInfo

Retrieves the type information for an object, which can be used to get the type information for an interface.(Inherited from Attribute.)

System_CAPS_pubinterface System_CAPS_privmethod _AttributeGetTypeInfoCount

Retrieves the number of type information interfaces that an object provides (either 0 or 1).(Inherited from Attribute.)

System_CAPS_pubinterface System_CAPS_privmethod _AttributeInvoke

Provides access to properties and methods exposed by an object.(Inherited from Attribute.)

When you apply this attribute to a data field, you must follow the guidelines for the use of the attributes. For more information, see ASP.NET Dynamic Data Guidelines.

See an online example of this feature: Run.

The following example shows how to use the DisplayFormatAttribute to customize formatting for a data field. The example performs the following steps:

  • Implements a metadata partial class and an associated metadata class.

  • In the associated metadata class, it applies the DisplayFormatAttribute attribute to specify the following results:

    • Display the text "[Null]" when a data field is empty.

    • Display currency data in locale specific currency format.

    • Display date information in short format (mm/dd/yy). This format also applies in edit mode.

using System;
using System.Web.DynamicData;
using System.ComponentModel.DataAnnotations;


[MetadataType(typeof(ProductMetaData))]
public partial class Product
{

}

public class ProductMetaData
{

    // Applying DisplayFormatAttribute
    // Display the text [Null] when the data field is empty.
    // Also, convert empty string to null for storing.
    [DisplayFormat(ConvertEmptyStringToNull = true, NullDisplayText = "[Null]")]
    public object Size;

    // Display currency data field in the format $1,345.50.
    [DisplayFormat(DataFormatString="{0:C}")]
    public object StandardCost;

    // Display date data field in the short format 11/12/08.
    // Also, apply format in edit mode.
    [DisplayFormat(ApplyFormatInEditMode=true, DataFormatString = "{0:d}")]
    public object SellStartDate;
}
Imports System
Imports System.Web.DynamicData
Imports System.ComponentModel.DataAnnotations


<MetadataType(GetType(ProductMetaData))> _
Partial Public Class Product

End Class

Public Class ProductMetaData

    ' Applying DisplayFormatAttribute

    ' Display the text [Null] when the data field is empty.
    ' Also, convert empty string to null for storing.
    <DisplayFormat(ConvertEmptyStringToNull:=True, NullDisplayText:="[Null]")> _
    Public Size As Object

    ' Display currency data field in the format such as $1,345.50.
    <DisplayFormat(DataFormatString:="{0:C}")> _
    Public StandardCost As Object

    ' Display date data field in the short format such as 11/12/08.
    ' Also, apply format in edit mode.
    <DisplayFormat(ApplyFormatInEditMode:=True, DataFormatString:="{0:d}")> _
    Public SellStartDate As Object

End Class

To compile the example, you need the following:

  • Microsoft Visual Studio 2008 Service Pack 1 or Visual Web Developer 2008 Express Edition Service Pack 1.

  • The AdventureWorksLT sample database. For information about how to download and install the SQL Server sample database, see Microsoft SQL Server Product Samples: Database on the CodePlex site. Make sure that you install the correct version of the sample database for the version of SQL Server that you are running (Microsoft SQL Server 2005 or Microsoft SQL Server 2008).

  • A data-driven Web site. This enables you to create a data context for the database and the class that contains the data field to customize. For more information, see Walkthrough: Creating a New Dynamic Data Web Site using Scaffolding.

Universal Windows Platform
Available since 8
.NET Framework
Available since 3.5
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 3.0

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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