Class ViewModelField<T>

View model class that represents a field on a form. For example, "FirstName", "LastName", "Age", or "BirthDate". It provides properties for validation, visibility, and enabled. If you're using Benday.Presentation.Controls, those field controls will bind to the properties on this class with a single, simple binding expression.

Inheritance

object

ViewModelBase

ViewModelField<T>

Implements

INotifyPropertyChanged

IVisibleField

Inherited Members

ViewModelBase.RaisePropertyChanged(string)

ViewModelBase.PropertyChanged

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

Namespace: Benday.Presentation

Assembly: Benday.Presentation.dll

Syntax

public class ViewModelField<T> : ViewModelBase, INotifyPropertyChanged, IVisibleField

Type Parameters

Name	Description
T	Data type being wrapped by this field. Typically types like int, string, DateTime, etc.

Constructors

ViewModelField()

Declaration

public ViewModelField()

ViewModelField(T)

Declaration

public ViewModelField(T initialValue)

Parameters

Type	Name	Description
T	initialValue

Properties

IsEnabled

Should the field be enabled on the form?

Declaration

public bool IsEnabled { get; set; }

Property Value

Type	Description
bool

IsValid

Represents the validation status of this field. If IsValid is false, then ValidationMessage should contain a message. NOTE: this class does not perform any validation logic on its own. It is up to the consumer to set this value and if necessary the ValidationMessage value.

Declaration

public bool IsValid { get; set; }

Property Value

Type	Description
bool

IsVisible

Should the field be visible on the form?

Declaration

public bool IsVisible { get; set; }

Property Value

Type	Description
bool

ValidationMessage

Gets or sets the ValidationMessage property. This observable property. This is intended to be displayed when IsValid is false. NOTE: this class does not do any validation logic on its own. It is up to the consumer to set this value.

Declaration

public string ValidationMessage { get; set; }

Property Value

Type	Description
string

Value

Gets or sets the Value of this field. This observable property.

Declaration

public T Value { get; set; }

Property Value

Type	Description
T

Methods

RaiseOnValueChanged()

Raises the OnValueChanged event.

Declaration

public virtual void RaiseOnValueChanged()

ToString()

Returns the Value property of this field as a string. If Value is null, returns String.Empty.

Declaration

public override string ToString()

Returns

Type	Description
string

Overrides

object.ToString()

Exceptions

Type	Condition
InvalidOperationException

Events

OnValueChanged

Event raised when the Value property changes on this field.

Declaration

public event EventHandler? OnValueChanged

Event Type

Type	Description
EventHandler

Implements

INotifyPropertyChanged

IVisibleField