Hi guys,
I am building a string in code that is a mathematical formula, based on a
lot of criteria specified by the user. Once the formula is complete, I want
to evaluate it to get a result. For example:
dim strFormula as String
strFormula = "((2 + 2) * 3) / 4) - 5"
Once I have this formula, I want to evaluate it and get the result: -2.
Any tips on how I can do this?
Also, is there a way to check if the formula is valid (i.e. I didn't miss
any parenthesis or anything)? I guess I could try to evaluate it, and stick
it in a try - catch block.
Thanks for your time and help!
Wade
4  10692 
Three basic options:
1. Write your own postfix/prefix based expressions evaluator
2. Use Reflection.Emit to generate a function to evaluate this formula and
then execute that
3. Use the javascript eval function. There was a example posted in response
to a similar query a week or two back in this group on how to do the exact
same thing.
Rgds,
Anand M
VB.NET MVP http://www.dotnetindia.com
"Wade" wrote: Hi guys,
I am building a string in code that is a mathematical formula, based on a
lot of criteria specified by the user. Once the formula is complete, I want
to evaluate it to get a result. For example:
dim strFormula as String
strFormula = "((2 + 2) * 3) / 4) - 5"
Once I have this formula, I want to evaluate it and get the result: -2.
Any tips on how I can do this?
Also, is there a way to check if the formula is valid (i.e. I didn't miss
any parenthesis or anything)? I guess I could try to evaluate it, and stick
it in a try - catch block.
Thanks for your time and help!
Wade
The solution from the following website proved to be the perfect solution to
my problem: http://www.codeproject.com/vb/net/ma..._evaluator.asp
Thanks!
"Anand[MVP]" <An******@discu ssions.microsof t.com> wrote in message
news:D8******** *************** ***********@mic rosoft.com... Three basic options:
1. Write your own postfix/prefix based expressions evaluator
2. Use Reflection.Emit to generate a function to evaluate this formula and
then execute that
3. Use the javascript eval function. There was a example posted in
response to a similar query a week or two back in this group on how to do the exact
same thing.
Rgds,
Anand M
VB.NET MVP
http://www.dotnetindia.com
"Wade" wrote:
Hi guys,
I am building a string in code that is a mathematical formula, based on
a lot of criteria specified by the user. Once the formula is complete, I
want to evaluate it to get a result. For example:
dim strFormula as String
strFormula = "((2 + 2) * 3) / 4) - 5"
Once I have this formula, I want to evaluate it and get the result: -2.
Any tips on how I can do this?
Also, is there a way to check if the formula is valid (i.e. I didn't
miss any parenthesis or anything)? I guess I could try to evaluate it, and
stick it in a try - catch block.
Thanks for your time and help!
Wade
"Wade" <wwegner23NOEMA ILhotmail.com> schrieb: I am building a string in code that is a mathematical formula, based on a
lot of criteria specified by the user. Once the formula is complete, I
want
to evaluate it to get a result. For example:
dim strFormula as String
strFormula = "((2 + 2) * 3) / 4) - 5"
Once I have this formula, I want to evaluate it and get the result: -2.
MathLib
<URL:http://www.palmbytes.d e/content/dotnet/mathlib.htm>
--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/> This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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