What is the difference between Boolean and [Boolean]?
I ran some code through an automatic translator for C# to VB, and it translate开发者_高级运维d some code like this:
Public Property Title As [String]
How is this different to
Public Property Title As String
and why do both exist?
String
is a keyword. If you want to use a keyword as an identifier, you'll have to enclose it in brackets. [String]
is an identifier. String
keyword always refers to System.String
class while [String]
can refer to your own class named String
in the current namespace. Assuming you have Imports System
, both refer to the same thing most of the time but they can be different:
Module Test
Class [String]
End Class
Sub Main()
Dim s As String = "Hello World" // works
Dim s2 As [String] = "Hello World" // doesn't work
End Sub
End Module
The primary reason for existence of [ ]
for treating keywords as identifiers is interoperability with libraries from other languages that may use VB keywords as type or member names.
[] allows you to use VBs keywords as identifiers, just like @ in c#. it is useless here.
In that example, they do nothing.(*) You can use brackets to use reserved words as identifiers, though. E.g.: Dim [String] as String
EDIT:
(*) Unless they've defined their own class called [String]
that they could be referring to
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