![]() Local constants are accessible only from within their procedure or block. You can also use AscW if you call it with a constant String or Char argument, since that can be evaluated at compile time. However, you can use conversion keywords such as CByte and CShort. ![]() You cannot use variables or functions in initializer. You can use arithmetic and logical operators to combine such elements. The expression can be any combination of literals, other constants that are already defined, and enumeration members that are already defined. You use initializer to supply an expression to be assigned to the constant. You must initialize the value of every constant in constantlist. However, you cannot declare several constants to be of the same type by using a common As clause. You can specify different data types for different constants by using a separate As clause for each variable you declare. If neither datatype nor initializer is present, the data type defaults to Object.ĭifferent Types. If you specify both datatype and initializer, the data type of initializer must be convertible to datatype. If you do not specify datatype, the constant takes the data type of initializer. You can specify any data type or the name of an enumeration.ĭefault Type. The Const statement can declare the data type of a variable. Multiple constants are separated by commas.ĭata Types. You can declare several constants in the same declaration statement, specifying the constantname part for each one. You cannot use any of these keywords when declaring a constant.Īt procedure level, you cannot use Shadows or any access modifiers to declare local constants. By default, all constants are Shared, Static, and ReadOnly. An attribute contributes information to the assembly's metadata, which is not meaningful for temporary storage such as local constants. You can apply attributes only to member constants, not to local constants. ![]() A constant declared at module level, outside any procedure, is a member constant it is a member of the class, structure, or module that declares it.Ī constant declared at procedure level is a local constant it is local to the procedure or block that declares it.Īttributes. You can adjust their access levels with the access modifiers. Class and module member constants (outside any procedure) default to private access, and structure member constants default to public access. Local constants (inside a procedure) default to public access, and you cannot use any access modifiers on them. For more information, see Declaration Contexts and Default Access Levels. This means the declaration context for a variable must be a class, structure, module, procedure, or block, and cannot be a source file, namespace, or interface. You can use Const only at module or procedure level. If in a later version you need to redefine the value, the Const statement is the only place you need to make a change. You can define the constant just once and use it in many places in your code. A name is easier to remember than a value. If you have a value that never changes in your application, you can define a named constant and use it in place of a literal value. Expression that is evaluated at compile time and assigned to the constant. ![]() List of constants being declared in this statement.Įach constant has the following syntax and parts:Ĭonstantname = initializer Part Use this to redeclare and hide a programming element in a base class. Can be Public, Protected, Friend, Protected Friend, Private, or Private Protected. Use this to specify what code can access these constants. See Attribute List in angle brackets (" "). List of attributes that apply to all the constants declared in this statement. Declares and defines one or more constants.
0 Comments
Leave a Reply. |