How can I convert a text to integer

[meki_2118]

hi. how can I convert a string to integer? I'm doing a program in VB were you are required to input a mathematical formula in a single input box and value each of the integer. But when I use the Left command, the formula of the textbox are converted into string type and won't compute the value as in the formula indicated. I really need your help. thanks..

[Dave Kreskowiak]

There is nothing built into VB.NET or the .NET Framework that's going to evaluate expressions typed into a textbox. You have to create your own expression parsing engine to break the input down into something you can do the math on, piece-by-piece. Google for "Reverse Polish Notation" for an intro to expression engines. There are certainly other implementations to do this, but RPN is good place to start.

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Dave Kreskowiak Microsoft MVP Visual Developer - Visual Basic
     2006, 2007

[V 2]

Hi, If U want to convert text in to integer then simply U can use it:- dim s as string dim i as integer s="200" i=val(s) 'This function converts the string in integer Best Of Luck:rose:

[Colin Angus Mackay]

Did you read the OP's question? He said the text box contains a "mathematical formula".

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[Pete OHanlon]

Have you considered looking at this[^] article to get an understanding on evaluating formulae in a textbox. I know it's in C#, but using a tool like Reflector it's relatively simple to revert the IL into VB.NET.

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