Converting byte array to string in C#

Question

Is there an easy way to convert a byte array to a string so the following unit test passes? I can't find an encoding that works for all values.

  [TestMethod]
  public void TestBytToString()
  {
     byte[] bytArray = new byte[256];
     for (int i = 0; i < bytArray.Length; i++)
     {
        bytArray[i] = (byte)i;
     }
     string x = System.Text.Encoding.Default.GetString(bytArray);
     for (int i = 0; i < x.Length; i++)
     {
        int y = (int)x[i];
        Assert.AreEqual(i, y);
     }
  }

`Array.ConvertAll` should work for creating a `char[]`, which you can pass to a string constructor. — Ben Voigt, Jul 24 '13 at 20:46
Avoiding the "why would you do this?" question, the only encoding this operation would be valid in would be ASCII, I think. — JerKimball, Jul 24 '13 at 20:59
When I got your code and tested with the following , test passes `string x = new string(bytArray.Select(Convert.ToChar).ToArray());` Credit goes to [@Ricky](http://stackoverflow.com/a/9573587/1991801) — Mechanical Object, Jul 24 '13 at 21:56

score 1 · Answer 1 · answered Jul 24 '13 at 20:41

1

The System.Text.Encoding.UTF8 should do a trick for you.

answered Jul 24 '13 at 20:41

Tigran

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What if it's not in UTF8? – It'sNotALie. Jul 24 '13 at 20:41
So what encoding is it? If it's a ASCII, it still in the margins of UTF8, which is famous for shrinking to the necessary size. – Tigran Jul 24 '13 at 20:43
When I use UTF8 it fails with Expected: <128>, Actual: <65533>. – user2227596 Jul 24 '13 at 20:52

score 1 · Answer 2 · answered Jul 24 '13 at 20:42

1

string x = Encoding.UTF8.GetString(bytArray, 0, bytArray.Length);

answered Jul 24 '13 at 20:42

Nick

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When I use the above it fails with Expected: <128>, Actual: <65533>. – user2227596 Jul 24 '13 at 20:53

score 1 · Answer 3 · answered Jul 24 '13 at 20:49

1

var str = System.Text.Encoding.Default.GetString(bytArray);

answered Jul 24 '13 at 20:49

1Mojojojo1

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When I use the above it fails whe Expected: <128>, Actual: <8364> – user2227596 Jul 24 '13 at 21:01

score 0 · Answer 4 · answered Jul 24 '13 at 21:10

As far as i know everthing above value 127 in byte is considered a negative number and as char can only take positive values it results with an unknown char in every encoding you take.

You might want to convert the byte array to unsigned short (ushort) and then to string...

score 0 · Accepted Answer · answered Jul 24 '13 at 22:13

This worked:

  [TestMethod]
  public void TestBytToString()
  {
     byte[] bytArray = new byte[256];
     ushort[] usArray = new ushort[256];
     for (int i = 0; i < bytArray.Length; i++)
     {
        bytArray[i] = (byte)i;

     }

     string x = System.Text.Encoding.Default.GetString(bytArray);
     for (int i = 0; i < x.Length; i++)
     {
        int y = System.Text.Encoding.Default.GetBytes(x.Substring(i, 1))[0];
        Assert.AreEqual(i, y);
     }
  }

Converting byte array to string in C#

5 Answers5