C# Cookbook

16.10. Converting Pointers to a Byte[ ], SByte[ ],or Char[ ] to a String

Problem

You have obtained a pointer to a byte array, an sbyte array, or a char array. You want to convert this array into its string equivalent.

Solution

Use one of the string object’s constructors that build a string from either a byte*, sbyte*, or char* passed in as a parameter. The following overloaded ConvertToString methods accept a byte[], an sbyte[], or a char[] and return the equivalent string object created from these arrays:

public string ConvertToString(byte[] arr)
{
    unsafe
    {
        string returnStr;
        fixed(byte* fixedPtr = arr)
        {
            returnStr = new string((sbyte*)fixedPtr);
        }
    }

    return (returnStr);
}

public string ConvertToString(sbyte[] arr)
{
    unsafe
    {
        string returnStr;
        fixed(sbyte* fixedPtr = arr)
        {
            returnStr = new string(fixedPtr);
        }
    }

    return (returnStr);
}

public string ConvertToString(char[] arr)
{
    unsafe
    {
        string returnStr;
        fixed(char* fixedPtr = arr)
        {
            returnStr = new string(fixedPtr);
        }
    }

    return (returnStr);
}

The following code calls these methods, passing in one of the required array types:

Console.WriteLine(ConvertToString(new byte[3] {0x61,0x62,0x63}));
Console.WriteLine(ConvertToString(new char[3] {'a','b','c'}));
Console.WriteLine(ConvertToString(new sbyte[3] {0x61,0x62,0x63}));

Discussion

The System.String constructor that takes an sbyte* in the Solution code is expecting a null-terminated string in the buffer. There are also constructors on System.String that take an sbyte* and default to Unicode, ...