I need critique on this code

Sundeepan Sen

Just got back into writing code after 10 years. This is a infix to postfix converter. Can someone please critique this... thanks

using System;
using System.Collections;
using System.Text;
using System.Text.RegularExpressions;
using System.Collections.Generic;

namespace Infix2Postfix
{
public class Program
{
static void Main(string[] args)
{
#region variable declarations
//declare and initialize the string to accept an expression in infix notation
String stringInfix = "a+b/c-d";

        StringBuilder SbPostfix = new StringBuilder();
        Stack<char> stackGeneral = new Stack<char>();
        Stack<char> stackOperator = new Stack<char>();
        char\[\] tempArray = stringInfix.ToCharArray();

        Array.Reverse(tempArray);
        Regex regexAlphaNum = new Regex("\[a-zA-Z0-9\]");
        char temp;

        #endregion

        #region logic

        foreach (char ch in tempArray)
            stackGeneral.Push(ch);

        foreach (char ch in stackGeneral)
        {
            if (regexAlphaNum.IsMatch(Convert.ToString(ch)))
                SbPostfix.Append(ch);
            else if (stackOperator.Count == 0)
                stackOperator.Push(ch);
            else if (stackOperator.Count != 0)
                switch (ch)
                {
                    case '+':
                        temp = stackOperator.Peek();
                        if (temp == '\*' || temp == '/')
                        {
                            while (stackOperator.Count > 0)
                                SbPostfix.Append(stackOperator.Pop());
                            stackOperator.Push(ch);
                        }
                        else
                            stackOperator.Push(ch);
                        break;
                    case '-':
                        temp = stackOperator.Peek();
                        if (temp == '\*' || temp == '/')
                        {
                            while (stackOperator.Count > 0)
                                SbPostfix.Append(stackOperator.Pop());
                            stackOperator.Push(ch);
                        }
                        else
                            stackOperator.Push(ch);

PIEBALDconsult

I don't think you need tempArray. How does it handle malformed input? Here's[^] my infix-to-postfix code; there are others on here.

Dan Mos

Here I am criticizing it :-D It's too long and too late at night for me :zzz: . Now it's joke time :cool

Ennis Ray Lynch Jr

I would fire you on the spot for putting regions in a method and not maintaining consistent capitalization of variables.

Need custom software developed? I do custom programming based primarily on MS tools with an emphasis on C# development and consulting. A man said to the universe: "Sir I exist!" "However," replied the universe, "The fact has not created in me A sense of obligation." --Stephen Crane

Sundeepan Sen

lol...I know exactly which variable name you are referring to.

Sundeepan Sen

Why are regions in a method a bad idea? I ask this risking sounding like a fool.

Dan Mos

Regions are intended to be used in GROUPING methods not splitting one method's body. [EDIT] Example:

#region Events//put here all/most of the event(s) handling code

#region Drawing//put here all the drawing methods

#region YouNameIt// put here all the...

[/EDIT]

Sundeepan Sen

It only handles inputs in a*b-c/d format. The code is very basic, written in an non elegant way. I will look at your code, it might give me some insights.

Sundeepan Sen

Ahh...I understand. Thanks!

Sundeepan Sen

LOL-i.pop();

Dan Mos

for nothing

Sundeepan Sen

Oh c'mon my friend...your statement helped me more than any other reading I did today :-D

Dan Mos

Ohh, well, in that case, glad that I could help :)

Dan Mos

and i.push() :-D

Sundeepan Sen

Sounds like candy...haha

AspDotNetDev

Also, if you are using a region in a method, it is a sure sign you should put some of your logic into another method and just call that method from your original method.

[Forum Guidelines]

Sundeepan Sen

Thank you for your reply and the link! :-O

AspDotNetDev

You are welcome. FYI, the link is part of my generic signature and was not targeted at you specifically. Still, if you haven't read it yet, it is advisable that you do so. :)

[Forum Guidelines]

PIEBALDconsult

That may be only a personal or company standard. One can use regions wherever one darn well wants to. I generally use them only to group methods and properties, but I may also use seperate files (partial classes) for that purpose if the code becomes large enough. In my RPN transformer I use regions to mark off less-important code that the reader may not be interested in -- it should at least help with documentation and readability -- I don't want to read through a bunch of error-handling code when I'm trying to get a feel for the process flow of a method.

PIEBALDconsult

Yes, but the additional method calls could become a bottleneck in a tight loop. And the resultant code could be even less readable. You need to examine each case on its own.