Easy way to reverse each word in a sentence

Question

Example:

string str = \"I am going to reverse myself.\";
string strrev = \"I ma gniog ot esrever .flesym\"; //An easy way to achieve this

A

Answer 1

Well, here's a LINQ solution:

var reversedWords = string.Join(" ",
      str.Split(' ')
         .Select(x => new String(x.Reverse().ToArray())));

If you're using .NET 3.5, you'll need to convert the reversed sequence to an array too:

var reversedWords = string.Join(" ",
      str.Split(' ')
         .Select(x => new String(x.Reverse().ToArray()))
         .ToArray());

In other words:

• Split on spaces
• For each word, create a new word by treating the input as a sequence of characters, reverse that sequence, turn the result into an array, and then call the string(char[]) constructor
• Depending on framework version, call ToArray() on the string sequence, as .NET 4 has more overloads available
• Call string.Join on the result to put the reversed words back together again.

Note that this way of reversing a string is somewhat cumbersome. It's easy to create an extension method to do it:

// Don't just call it Reverse as otherwise it conflicts with the LINQ version.
public static string ReverseText(this string text)
{
    char[] chars = text.ToCharArray();
    Array.Reverse(chars);
    return new string(chars);
}

Note that this is still "wrong" in various ways - it doesn't cope with combining characters, surrogate pairs etc. It simply reverses the sequence of UTF-16 code units within the original string. Fine for playing around, but you need to understand why it's not a good idea to use it for real data.