/// <summary>
/// Creates a backing field for the given property
/// </summary>
/// <param name="property">The code property</param>
/// <param name="type">The type of the property</param>
/// <param name="initialValue">The initial value expression for the field</param>
/// <returns>A reference to the generated backing field</returns>
public static CodeFieldReferenceExpression CreateBackingField(this CodeMemberProperty property, CodeTypeReference type, CodeExpression initialValue)
{
var reference = CodeDomHelper.GetOrCreateUserItem <CodeFieldReferenceExpression>(property, CodeDomHelper.BackingFieldKey);
if (reference == null)
{
var field = new CodeMemberField()
{
Attributes = MemberAttributes.Private,
Name = "_" + property.Name.ToCamelCase(),
Type = type ?? new CodeTypeReference(typeof(object))
};
field.WriteDocumentation(string.Format("The backing field for the {0} property", property.Name));
property.DependentMembers(true).Add(field);
if (initialValue != null)
{
field.InitExpression = initialValue;
}
reference = new CodeFieldReferenceExpression(new CodeThisReferenceExpression(), field.Name);
CodeDomHelper.SetUserItem(property, CodeDomHelper.BackingFieldRefKey, reference);
CodeDomHelper.SetUserItem(property, CodeDomHelper.BackingFieldKey, field);
}
return(reference);
}
/// <summary>
/// Generates an OnChanging-pattern for the given property
/// </summary>
/// <param name="property">The code property</param>
/// <returns></returns>
public static CodeStatement CreateOnChangingEventPattern(this CodeMemberProperty property)
{
var changingEvent = new CodeMemberEvent()
{
Name = property.Name + "Changing",
Type = new CodeTypeReference(typeof(EventHandler).Name),
Attributes = MemberAttributes.Public | MemberAttributes.Final
};
changingEvent.WriteDocumentation(string.Format("Gets fired before the {0} property changes its value", property.Name));
var eventType = new CodeTypeReference(typeof(EventArgs).Name);
var eventData = new CodeFieldReferenceExpression(new CodeTypeReferenceExpression(eventType), "Empty");
var onChanging = CreateOnChangedMethod(changingEvent, eventType);
var dependent = property.DependentMembers(true);
dependent.Add(onChanging);
dependent.Add(changingEvent);
var onChangedRef = new CodeMethodReferenceExpression(new CodeThisReferenceExpression(), onChanging.Name);
return(new CodeExpressionStatement(new CodeMethodInvokeExpression(onChangedRef, eventData)));
}
/// <summary>
/// Generates an OnChanged-pattern for the given property
/// </summary>
/// <param name="property">The code property</param>
/// <returns>The statement to call the OnChanged method for the given property</returns>
public static CodeStatement CreateOnChangedEventPattern(this CodeMemberProperty property, CodeTypeReference eventType, CodeExpression eventData)
{
CodeTypeReference handlerType;
if (eventType == null)
{
handlerType = typeof(EventHandler).ToTypeReference();
}
else
{
handlerType = typeof(EventHandler <>).ToTypeReference(eventType);
}
var changedEvent = new CodeMemberEvent()
{
Name = property.Name + "Changed",
Type = handlerType,
Attributes = MemberAttributes.Public | MemberAttributes.Final
};
changedEvent.WriteDocumentation(string.Format("Gets fired when the {0} property changed its value", property.Name));
if (eventType == null)
{
eventType = new CodeTypeReference(typeof(EventArgs).Name);
eventData = new CodeFieldReferenceExpression(new CodeTypeReferenceExpression(eventType), "Empty");
}
var onChanged = CodeDomHelper.CreateRaiseMethod(changedEvent, eventType);
var dependent = property.DependentMembers(true);
dependent.Add(onChanged);
dependent.Add(changedEvent);
var onChangedRef = new CodeMethodReferenceExpression(new CodeThisReferenceExpression(), onChanged.Name);
return(new CodeExpressionStatement(new CodeMethodInvokeExpression(onChangedRef, eventData)));
}
