Calculations

[Pitaridis Aristotelis]

Is there a way to make a calculation stored in a string. For example:

Dim A as string = "4 * 10 ^ 8"

Dim Result as Decimal = Calculate(A)

[=?Utf-8?B?VGhlQ3Jhc2g=?=]

"Pitaridis Aristotelis" wrote:

Is there a way to make a calculation stored in a string. For example:

Dim A as string = "4 * 10 ^ 8"

Dim Result as Decimal = Calculate(A)

I don't think so :(

[\(O\)enone]

Pitaridis Aristotelis wrote:

Is there a way to make a calculation stored in a string. For example:

Dim A as string = "4 * 10 ^ 8"

Dim Result as Decimal = Calculate(A)

There are many ways to do this, some better than others and some more
complex than others...

Try the following Google search which should provide some answers:

http://www.google.com/search?hl=en&q=%22vb.net%22+eval

--

(O)enone

[Tom Shelton]

On Oct 25, 3:51 am, "Pitaridis Aristotelis" <[e-mail]>
wrote:

Is there a way to make a calculation stored in a string. For example:

Dim A as string = "4 * 10 ^ 8"

Dim Result as Decimal = Calculate(A)

As an alternative:

http://groups.google.com/group/micro...e=UTF-8&rnum=1

Be aware, that you will probably want to validate any expressions you
pass to this function, because it will run arbitrary jscript code.

--
Tom Shelton

[Pitaridis Aristotelis]

? "Tom Shelton" <to*********@comcast.net?????? ??? ??????
news:11**********************@k35g2000prh.googlegr oups.com...

On Oct 25, 3:51 am, "Pitaridis Aristotelis" <[e-mail]>
wrote:

>Is there a way to make a calculation stored in a string. For example:

Dim A as string = "4 * 10 ^ 8"

Dim Result as Decimal = Calculate(A)

As an alternative:

http://groups.google.com/group/micro...e=UTF-8&rnum=1

Be aware, that you will probably want to validate any expressions you
pass to this function, because it will run arbitrary jscript code.

--
Tom Shelton

I was looking for vb.net code which will handle the whole thing. I used
sometime an example that I downloaded from the internet but I can not find
it.

[Bruce W. Roeser]

You are looking for an algorithm that's called a "recursive descent parser".
Doing this type of thing is an exercise that we had to do in programming
classes 35 years ago.

I'm a little bit amazed that something like this doesn't exist in the .Net
framework. Even in VBScript I think there's the "eval" function that might
have limited parsing capability. Still ... this is a good programming
exercise to learn how to write recursive functions.

If you want to create your own class function to do this go get a
fundamental programming book and study the chapters on recursion. I'd be
real surprised if you couldn't find a good writeup on how to do this.

-bwr-

"Pitaridis Aristotelis" <pi*******@hotmail.comwrote in message
news:47***********************@news.sunsite.dk...

Is there a way to make a calculation stored in a string. For example:

Dim A as string = "4 * 10 ^ 8"

Dim Result as Decimal = Calculate(A)

[Tom Shelton]

On Oct 26, 3:25 am, "Pitaridis Aristotelis" <[e-mail]>
wrote:

? "Tom Shelton" <[e-mail]?????? ??? ??????news:11**********************@k35g2000prh.go oglegroups.com...

On Oct 25, 3:51 am, "Pitaridis Aristotelis" <[e-mail]>
wrote:

Is there a way to make a calculation stored in a string. For example:

Dim A as string = "4 * 10 ^ 8"

Dim Result as Decimal = Calculate(A)

As an alternative:

http://groups.google.com/group/micro...languages.vb/m...

Be aware, that you will probably want to validate any expressions you
pass to this function, because it will run arbitrary jscript code.

--
Tom Shelton

I was looking for vb.net code which will handle the whole thing. I used
sometime an example that I downloaded from the internet but I can not find
it.- Hide quoted text -

- Show quoted text -

Why does it have to be VB.NET. With a few lines of JScript code
(a .net language), you can accomplish what you're asking.

If you simply want the experience of doing this sort of thing, then
great. It is a good programming exercise - I MIGHT even have some old
C++ and VB5 code somewhere that does this (I wrote the C++ code for an
exercise in school, and latter adapted it to VB5).

--
Tom Shelton