无法在C＃中将char数组转换为int值

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?

Answer 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 .

Answer 2

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.

Answer 3

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);