Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
886 views
in Technique[技术] by (71.8m points)

vb.net - Why can't I project ToString() in VB?

If you try to compile the query below in Visual Basic .NET, it fails.

From x In {1, 2} Select x.ToString()

The error given by the compiler is:

Range variable name cannot match the name of a member of the 'Object' class.

There is nothing wrong with the equivalent C# query, though:

from x in new[]{1, 2} select x.ToString()

This does not happen with the ToString overload that takes a format (it is a member of Int32, not Object). It does happen with other members of Object, as long as they don't take an argument: with GetType and GetHashCode it fails; with Equals(object) it compiles.

Why is this restriction in place, and what alternatives can I use?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

I couldn't tell you exacly why VB has this ridiculousness, but the simple workaround is to put the method call in parens.

Dim q = From x In {1, 2} Select (x.ToString())

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...