Can't cast char array into int value in C#

Question

I am making a caesar cipher and am trying to convert the char value of each letter into an int so the shift value can change it.

for (int i = 0; i < plainTextInput.Length; ++i)
{
   chars[i] = ((int)chars[i]) + shiftAmount;         
}

It says it cannot convert int into char. How do i fix this problem?

It seems like chars[] is an array of chars. If so, you need to cast it back to a char: chars[i]=(char)((int)chars[i])+shiftAmount; — Law Metzler
– Law Metzler, Commented Sep 30, 2011 at 2:35

Adam Lear · Accepted Answer · 2011-09-30 02:36:34Z

1

You have to explicitly cast it back:

for (int i = 0; i < plainTextInput.Length; ++i)
{
   chars[i] = (char)(((int)chars[i]) + shiftAmount);         
}

However, you're going to run into trouble pretty quickly once you shift past z.

answered Sep 30, 2011 at 2:36

Adam Lear♦

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Comments

dlev · Accepted Answer · 2011-09-30 02:36:18Z

0

When I compile that code, I get the following error message:

Cannot implicitly convert type 'int' to 'char'. An explicit conversion exists (are you missing a cast?)

Why yes, you are missing a cast:

chars[i] = (char)(((int)chars[i]) + shiftAmount);

answered Sep 30, 2011 at 2:36

dlev

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jason · Accepted Answer · 2011-09-30 02:42:26Z

0

By explicitly casting:

chars[i] = (char)(((int)chars[i]) + shiftAmount);

I'd rewrite your loop:

var enciphered = chars.Select(c => (char)((int)c + shiftAmount)).ToArray();

What are you planning to do if you shift to a non-printable character? Standard Caesar cipher wraps around. You should incorporate that.

answered Sep 30, 2011 at 2:36

jason

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