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eval function in vb.net?

Does anyone know how I can do an "eval" on a string?
I have a string back from a database equivalent to "5*6" how can I eval
this to an int type of value 30?
Taking this further, to evaluate custom vb functions ie
eval("5 * AvgPrice('partnum')")

I know about the databind eval function but I am not doing this where I
can use a databinder object

Thanks

Tony
Nov 19 '05 #1
4 3058
Vko
You can use the COM library : Microsoft Script Control

more details there : http://www.devx.com/vb2themax/Tip/18773

"Tony" wrote:
Does anyone know how I can do an "eval" on a string?
I have a string back from a database equivalent to "5*6" how can I eval
this to an int type of value 30?
Taking this further, to evaluate custom vb functions ie
eval("5 * AvgPrice('partnum')")

I know about the databind eval function but I am not doing this where I
can use a databinder object

Thanks

Tony

Nov 19 '05 #2
Tony wrote:
Does anyone know how I can do an "eval" on a string?
I have a string back from a database equivalent to "5*6" how can I eval
this to an int type of value 30?
Taking this further, to evaluate custom vb functions ie
eval("5 * AvgPrice('partnum')")


You can use Reflection.Emit to dynamically generate and execute code on
the fly. See
http://msdn.microsoft.com/library/de...tcalltopic.asp
for an example.

Anders Norås
http://dotnetjunkies.com/weblog/anoras/
Nov 19 '05 #3
One wayh to do this is to use the JScript engine. See:

http://www.gotdotnet.com/community/m...&Page=1#212576
--
Scott
http://www.OdeToCode.com/blogs/scott/
Does anyone know how I can do an "eval" on a string?
I have a string back from a database equivalent to "5*6" how can I
eval
this to an int type of value 30?
Taking this further, to evaluate custom vb functions ie
eval("5 * AvgPrice('partnum')")
I know about the databind eval function but I am not doing this where
I can use a databinder object

Thanks

Tony

Nov 19 '05 #4
On Mon, 10 Jan 2005 07:56:07 -0800, Scott Allen wrote:
One wayh to do this is to use the JScript engine. See:

http://www.gotdotnet.com/community/m...&Page=1#212576
--
Scott
http://www.OdeToCode.com/blogs/scott/


Thanks, I'll give this a go.

Tony
Nov 19 '05 #5

This thread has been closed and replies have been disabled. Please start a new discussion.

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