Dim ... AS ... New

Syntax

dim args as classname1 = new classname2

Arguments

classname1: The new class type being created.
classname1: The new class type being assigned. In most situations, classname1 and classname2 will be the same.

Description

Describes how to use the Dim ... AS ... New syntax to define and instantiate new class types in Xbasic.

Discussion

If you have a class type, such as SQL::Arguments, and you say dim args as new SQL::Arguments = new SQL::Arguments, then whatever was there to begin with will be overwritten with the brand new definition of SQL::Arguments.

dim args as SQL::Arguments
args.set("MyArg","MyArgValue")

 new SQL::Arguments()

In some situations, the class of the variable you create is different from the assigned class. For example, in the code below, a variable named Stream is initially defined as a System::IO::Stream type. Later in the example, the Stream variable is assigned a new System::IO::MemoryStream object. The System::IO::MemoryStream is a type of System::IO::Stream class. Both classes are found in the .NET framework, which can be called into using Xbasic:

dim Stream as System::IO::Stream = null_value()
dim ContentType as C
dim Length as N
dim Buffer as B
dim CallResult as CallResult
dim Container as A5Storage::DataContainer = null_value()

Stream = new System::IO::MemoryStream()
CallResult = A5Storage::DataContainer::Open(Container, "Provider='Disk';Container='c:\A5Webroot';")
if CallResult.Success
    if Container.WriteItemToStream(Stream, Length, ContentType, "Speak.a5w")
        Stream.Seek(0, System::IO::SeekOrigin::Begin)

        dim Reader as System::IO::BinaryReader = new System::IO::BinaryReader(Stream)
        Buffer = Reader.ReadBytes(Length)
        Stream.close()
    else
        CallResult = Container.CallResult
    end if
end if

if CallResult.Success
    showvar("Type: " + ContentType + crlf() + "Length: " + Length + crlf(2) + buffer, "Success")
else
    showvar(CallResult.Text, "Error")
end if