• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 526
  • Last Modified:

Converting a String to Int[]

I have the code below, and I am having some weird behaviour when trying to convert a string to an int array. I know all values in the string are numbers and would just like to convert them into an int array so I can do some LUHN checking.

Some issues

The first digit in convert is 4
when I do:

char test = convert[i];

I get 52'4'

where 52 is the ASCII value for 4.

System.Convert.ToInt32(convert[i])

I get 52 where I am really looking for 4.


If I do:

Any ideas?
public static int[] ConvertString(string convert)
        {
            int[] digits = new int[convert.length];
 
            for (int i = 0; i < convert.Length; i++)
            {
                digits[i] = System.Convert.ToInt32(convert[i]);
            }
 
            return digits;
        }

Open in new window

0
directxBOB
Asked:
directxBOB
  • 4
  • 2
  • 2
  • +2
2 Solutions
 
lucky_jamesCommented:
52'4'....
you need 4...you have got 52.
then you can find for ' and have 4.
you can you IndexOf method of string class, get this 4 in another string and can convert the new formed string to integer.
0
 
lucky_jamesCommented:
seems like you want only 4 then you can use :
str.Remove(0, str.IndexOf("'')); // this would remove 52'
str.Substring(0, str.Length -1); // this would remove last '
now str would have 4 only.

hope it helps.
0
 
Jaime OlivaresCommented:
The best way is to use string.Split() method to separate elements, and a List to build the array dynamically:
public static int[] ConvertString(string convert)
{
    string[] elems = convert.Split('\'');
    List<int> list = new List<int>;
 
    foreach (string s in elems)
    {
         if (s.Length > 0)
              list.Add(Convert.ToInt32(s));
    }
    return list.ToArray();
}

Open in new window

0
What does it mean to be "Always On"?

Is your cloud always on? With an Always On cloud you won't have to worry about downtime for maintenance or software application code updates, ensuring that your bottom line isn't affected.

 
REA_ANDREWCommented:
I believe that this function will be better for you I have just made.  This will only add digits to an int array and not fallover if your string to convert is l9ike 123456H

Andrew
        static int[] ConvertString(string convert)
        {
            List<int> intList = new List<int>();
            foreach (char c in convert)
            {
                if (char.IsDigit(c))
                    intList.Add((Int32)Char.GetNumericValue(c));
            }
            return intList.ToArray();
        }

Open in new window

0
 
evilrixSenior Software Engineer (Avast)Commented:
Subract '0' from the char returned by convert[i]
public static int[] ConvertString(string convert)
{
    int[] digits = new int[convert.Length];
 
    for (int i = 0; i < convert.Length; i++)
    {
        digits[i] = System.Convert.ToInt32(convert[i] - '0');
    }
 
    return digits;
}
static void Main(string[] args)
{
    ConvertString("01234");
}

Open in new window

0
 
REA_ANDREWCommented:
Oh and

Char.GetNumericValue

Solves that issue you are experiencing about the code being returned and not the actual value of the char

Andrew :-)
0
 
directxBOBAuthor Commented:
char x = 9;    //Character '9' = ASCII 57
int b;

b = x - '0';   //That is '9' - '0' = 57 - 48 = 9
0
 
REA_ANDREWCommented:
Bit of useless info but comparing both my function and that of evilrix , which both work I might point out, BUT

I am surprised to see that evilrix's function is on average 3.9 milliseconds faster than mine.  

foreach loops just have performance hits everywhere lol
0
 
evilrixSenior Software Engineer (Avast)Commented:
I suspect the difference is the overhead in calling Char.GetNumericValue and Char.IsDigit
0
 
REA_ANDREWCommented:
true :-)

0

Featured Post

VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

  • 4
  • 2
  • 2
  • +2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now