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EVAL() in .NET?

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UGrad

Programmer
Oct 15, 2002
40
CA
Hi,
I did some research on this, but I couldn't find any answer.

In classic ASP, I can use eval() to evaluate a string.
For example, if I do eval(len("test")>5), it will return false. Or if I do eval(len("test") > 1 and len("test") < 5), it will return true.

Is there a function in .Net equivalent to eval()??

Please help.
 
Eval really doesn't have a place in a compiled language. Besides, you don't need it to do what you showed in your post.

If eval(len("test")>5)

is the same as

if len("test")>5




if eval(len("test") > 1 and len("test") < 5)

is the same as

if (len("test") > 1 and len("test") < 5)


There is no need for the eval()



I used to rock and roll every night and party every day. Then it was every other day. Now I'm lucky if I can find 30 minutes a week in which to get funky. - Homer Simpson

Arrrr, mateys! Ye needs ta be preparin' yerselves fer Talk Like a Pirate Day! Ye has a choice: talk like a pira
 
The reason I asked is because I want to use eval() to evaluate a string. This string is an input from user.

Basically, I have a text box for user to type in a string. Then I evaluate the text in the box.

For example, user can type in:
datediff("d", now, "1/1/2006")

or

5*2-9+10/44 > 10

or

year(now) > 2006 and month(now) < 6


 
Check out this link:

Dynamic Code Execution

I used to rock and roll every night and party every day. Then it was every other day. Now I'm lucky if I can find 30 minutes a week in which to get funky. - Homer Simpson

Arrrr, mateys! Ye needs ta be preparin' yerselves fer Talk Like a Pirate Day! Ye has a choice: talk like a pira
 
I found the solution.


Set a reference in your app to "Microsoft Script Control 1.0" It is under the COM tab in references. Then the code is really simple.


Dim SC As New MSScriptControl.ScriptControl
SC.Language = "VBSCRIPT"
Label1.text = Convert.ToString(SC.Eval(TextBox1.Text))

TextBox1.text can be:
datediff("d", now, "1/1/2006") > 1
or
5*2-9+10/44 > 10
or
year(now) > 2006 and month(now) < 6



 
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