Cannot convert to bool error in VB but not C#

[Bill Dee]

In C# this line compiles and works fine:
if (Request.Params["something"] != null)

But when trying to convert this to VB.NET and changing it to:
if (Request.Params["something"] <> Nothing)
I get the following error: Compiler Error Message: BC30311: Value of type
'System.Collections.Specialized.NameValueCollection' cannot be converted to
'Boolean'

Anyone know why this works in C# but not VB? How do I fix this?

Basically I do not care what the value of the param is, I just want to know
whether its set to anything or not. If I try and check its value without
testing it for null, then I will receive an error from trying to access a
null object. So it seems I need a way to check for null in the first place,
but cannot figure out how to do this in VB.NET. Any ideas? Thank you.

 

[Cor Ligthert]

Hi Bill,

Probably

if Not (Request.Params("something") Is Nothing then

Cor

 

[Armin Zingler]

In C# this line compiles and works fine:
if (Request.Params["something"] != null)

But when trying to convert this to VB.NET and changing it to:
if (Request.Params["something"] <> Nothing)
I get the following error: Compiler Error Message: BC30311: Value of
type 'System.Collections.Specialized.NameValueCollection' cannot be
converted to 'Boolean'

Anyone know why this works in C# but not VB? How do I fix this?

Use the correct operator to compare references: Is

if bla is nothing then

or

if not bla is nothing then


--
Armin

How to quote and why:
http://www.plig.net/nnq/nquote.html
http://www.netmeister.org/news/learn2quote.html

 

[Herfried K. Wagner [MVP]]

In C# this line compiles and works fine:
if (Request.Params["something"] != null)

But when trying to convert this to VB.NET and changing it to:
if (Request.Params["something"] <> Nothing)

That's not VB.NET code!!!

\\\
If Request.Params("something") Is Nothing Then
...
End If
///

I get the following error: Compiler Error Message: BC30311: Value of type
'System.Collections.Specialized.NameValueCollection' cannot be converted to
'Boolean'

Anyone know why this works in C# but not VB? How do I fix this?

Fix your code to make it compile in VB.NET.

 

[Cor Ligthert]

But when trying to convert this to VB.NET and changing it to:

if (Request.Params["something"] <> Nothing)

That's not VB.NET code!!!

\\\
If Request.Params("something") Is Nothing Then
...
End If
///

That is not good !!!!

)))

Cor

 

[Herfried K. Wagner [MVP]]

Errata:

In C# this line compiles and works fine:
if (Request.Params["something"] != null)

But when trying to convert this to VB.NET and changing it to:
if (Request.Params["something"] <> Nothing)

That's not VB.NET code!!!

\\\
If Request.Params("something") Is Nothing Then

.... sorry, should read: 'If Not ... Is Nothing'.

 

[Herfried K. Wagner [MVP]]

Probably

if Not (Request.Params("something") Is Nothing then

.... won't compile!

 

[Chris Dunaway]

Use the correct operator to compare references: Is

if bla is nothing then

or

if not bla is nothing then

And soon to be availble in Whidbey: IsNot

if bla IsNot Nothing Then

or

'This one is strange!!
If Not bla IsNot Nothing Then

 

[Armin Zingler]

And soon to be availble in Whidbey: IsNot

if bla IsNot Nothing Then

Looking forward to.


--
Armin

How to quote and why:
http://www.plig.net/nnq/nquote.html
http://www.netmeister.org/news/learn2quote.html

 

[Cor Ligthert]

if Not (Request.Params("something") Is Nothing then

... won't compile!

if Not Request.Params("something") Is Nothing then

You are right I was looking at it, and thought there is something wrong but
what.
I should have put it in the IDE however I did not.

Thanks

Cor

 

[Cor Ligthert]

Hi Chris,

'This one is strange!!
If Not bla IsNot Nothing Then

I find "object Is Something", much nicer

However what would be the equivalent in C#

Just my thoughts about it.

Cor

 

[Larry Serflaten]

I find "object Is Something", much nicer

Wouldn't that be the same as:

If bla Is Nothing Then


LFS

 

[Al Reid]

Hey, Larry, are you making the move to VB.Net or just checking it out? Somehow, I didn't expect to see you here.