MetaEnum class

The MetaEnum class represents single or multi-select enumerations. When a new meta-enum is created, a meta-type with the McDataType property and McDataType.Enum value is registered. If an enumerator has been created, you can create a new field with the enumerator meta-type. The entity object property returns the selected item ID (Int32) or an array of selected item IDs (Int32[]).

Note: When you create and delete meta-enums, remember that you can modify a meta-model only in Design mode. See the MetaClassManager class section.

Getting an enumerator collection

Because the enumerator is an original meta-type, you can get all enumerators from the MetaClassManager.RegisteredTypes property.

Example: Find all enumerators

foreach(MetaFieldType type in DataContext.Current.MetaModel.RegisteredTypes)
{
if (type.McDataType == McDataType.Enum)
{
// The enumerator is found
}
}

Managing enumerators

The following methods from the MetaEnum class are useful when managing enumerators:

• Call AddItem, passing meta-type, item friendly name and order ID, to add an enum item to the enumerator.
• Call ChangeOrder, passing meta-type, item ID and new order ID, to rename an enum item.
• Call Create, passing type name, friendly name and MultyValue flag, to create a new enumerator.
• Call GetItems, passing meta-type, to get all enum items.
• Call IsUsed, passing meta-type, to determine whether the specified type is used in any meta-class.
• Call Remove , passing meta-type, to delete an enumerator.
• Call RemoveItem, passing meta-type and item ID, to remove an enum item.
• Call RenameItem, passing meta-type, item ID and the new enum name, to rename an enum item.
• Call UpdateItem, passing meta-type, item friendly name and order ID, to update an enum item.

Creating an enumerator

Call the Create method of the MetaEnum class, passing type name, friendly name and MultyValue flag to create a new enumerator.

Example: Create a new enumerator

MetaFieldType newEnum = MetaEnum.Create(enumName, enumFriendlyName, bMultyValue);

Creating an enum meta-field

If you created an enumerator, you can create a new field with the enumerator meta-type.

Example: Creation of enum meta-field

public MetaField CreateEnumField(string name, string friendlyName, string enumName, bool isNullable, string defaultValue, bool enumEditable)
{
if (name == null)
throw new ArgumentNullException("name");

if (friendlyName == null)
throw new ArgumentNullException("friendlyName");

AttributeCollection attr = new AttributeCollection();
attr.Add(McDataTypeAttribute.EnumEditable, enumEditable);
MetaField retVal = this.MetaClass.CreateMetaField(name, friendlyName, enumName, isNullable, defaultValue, attr);
return retVal;
}