Attribute Definition Macro Definitions

The LLBLGen Pro designer allows you to specify attribute definitions for elements, which are used to produce .NET attribute definitions in the generated sourcecode. To add attribute definitions to an element, you either use the Project Properties Editor or edit the attributes on the code generation info tab of the element: (Entity, Typed List, Typed View or Value Type). To make the definition as generic as possible (so the attribute definition can be defined at the project level in the Project Properties Editor), macros can be used. The following macros are supported for attribute definitions.

• $true. This is resolved to the trueKeyword value in the used language
• $false. This is resolved to the falseKeyword value in the used language
• $null. This is resolved to the nullKeyword value in the used language
• $typeof. This is resolved to the typeofKeyword value in the used language
• $=. This is resolved to the attributeAssignmentOperator definition in the used language
• $length. This is resolved to the length of the field the attributed is defined on.
• $precision. This is resolved to the precision of the field the attributed is defined on
• $scale. This is resolved to the scale of the field the attributed is defined on
• $byte. This resolves to the byteKeyword which is a cast keyword for casting the value specified after it to byte.
• $int16. This resolves to the int16Keyword which is a cast keyword for casting the value specified after it to short.
• $int32. This resolves to the int32Keyword which is a cast keyword for casting the value specified after it to int.
• $int64. This resolves to the int64Keyword which is a cast keyword for casting the value specified after it to long.
• $single. This resolves to the singleKeyword which is a cast keyword for casting the value specified after it to single/float.
• $double. This resolves to the doubleKeyword which is a cast keyword for casting the value specified after it to double.
• $decimal. This resolves to the decimalKeyword which is a cast keyword for casting the value specified after it to decimal.

The macros used in other areas like with additional interfaces, are supported as well. These have a slightly different syntax and are given below.

• {$GroupName}. This resolves to the name of the group the element is in, which is the group of the containing element in the case of a field
• {$Name}. This resolves to the name of the element
• {$FullName}. This resolves to the name of the element and the containing element which can be the containing entity's name or the group name
• {$ContainerName}. This resolves to the name of the containing element, if applicable, or an empty string if the element isn't contained inside another element (e.g. entities aren't contained in anything).

.NET Attribute definitions are defined using constants, it therefore might be necessary to specify a specific type for a constant. E.g. 10 is seen as an integer, but it might be necessary to define that as a byte or short/Int16. To do this, one should use the 5 specific cast keywords if the value specified is ambiguistic and by default is seen as a value of a different type: numbers without fraction are by default seen as integers by compilers and numbers with fraction are by default seen as doubles. To specify a cast, use the syntax: $typename(value). For example: $byte(10). This will resolve to either (byte)(10) for C#, or to CByte(10) for VB.NET. Not specifying the value in parenthesis could cause problems for vb.net and there's no checking done on this.

It's not necessary to wrap the attribute in [] characters for C# or <> characters for VB.NET nor is it necessary to append a '_' for VB.NET, this is done by the code generator automatically.