如何将字节[]转换为字符串?每次我尝试，我都
系统。Byte []
而不是数值。
另外，我如何得到十六进制而不是小数的值?
当前回答
非常快速的扩展方法(带反转):
public static class ExtensionMethods {
public static string ToHex(this byte[] data) {
return ToHex(data, "");
}
public static string ToHex(this byte[] data, string prefix) {
char[] lookup = new char[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
int i = 0, p = prefix.Length, l = data.Length;
char[] c = new char[l * 2 + p];
byte d;
for(; i < p; ++i) c[i] = prefix[i];
i = -1;
--l;
--p;
while(i < l) {
d = data[++i];
c[++p] = lookup[d >> 4];
c[++p] = lookup[d & 0xF];
}
return new string(c, 0, c.Length);
}
public static byte[] FromHex(this string str) {
return FromHex(str, 0, 0, 0);
}
public static byte[] FromHex(this string str, int offset, int step) {
return FromHex(str, offset, step, 0);
}
public static byte[] FromHex(this string str, int offset, int step, int tail) {
byte[] b = new byte[(str.Length - offset - tail + step) / (2 + step)];
byte c1, c2;
int l = str.Length - tail;
int s = step + 1;
for(int y = 0, x = offset; x < l; ++y, x += s) {
c1 = (byte)str[x];
if(c1 > 0x60) c1 -= 0x57;
else if(c1 > 0x40) c1 -= 0x37;
else c1 -= 0x30;
c2 = (byte)str[++x];
if(c2 > 0x60) c2 -= 0x57;
else if(c2 > 0x40) c2 -= 0x37;
else c2 -= 0x30;
b[y] = (byte)((c1 << 4) + c2);
}
return b;
}
}
在上面的速度测试中击败所有其他人:
=== Long string test BitConvertReplace calculation Time Elapsed 2415 ms StringBuilder calculation Time Elapsed 5668 ms LinqConcat calculation Time Elapsed 11826 ms LinqJoin calculation Time Elapsed 9323 ms LinqAgg calculation Time Elapsed 7444 ms ToHexTable calculation Time Elapsed 1028 ms ToHexAcidzombie calculation Time Elapsed 1035 ms ToHexPatrick calculation Time Elapsed 814 ms ToHexKurt calculation Time Elapsed 1604 ms ByteArrayToHexString calculation Time Elapsed 1330 ms === Many string test BitConvertReplace calculation Time Elapsed 2238 ms StringBuilder calculation Time Elapsed 5393 ms LinqConcat calculation Time Elapsed 9043 ms LinqJoin calculation Time Elapsed 9131 ms LinqAgg calculation Time Elapsed 7324 ms ToHexTable calculation Time Elapsed 968 ms ToHexAcidzombie calculation Time Elapsed 969 ms ToHexPatrick calculation Time Elapsed 956 ms ToHexKurt calculation Time Elapsed 1547 ms ByteArrayToHexString calculation Time Elapsed 1277 ms
其他回答
下面是一个字节数组(byte[])的扩展方法，例如:
var b = new byte[] { 15, 22, 255, 84, 45, 65, 7, 28, 59, 10 };
Console.WriteLine(b.ToHexString());
public static class HexByteArrayExtensionMethods
{
private const int AllocateThreshold = 256;
private const string UpperHexChars = "0123456789ABCDEF";
private const string LowerhexChars = "0123456789abcdef";
private static string[] upperHexBytes;
private static string[] lowerHexBytes;
public static string ToHexString(this byte[] value)
{
return ToHexString(value, false);
}
public static string ToHexString(this byte[] value, bool upperCase)
{
if (value == null)
{
throw new ArgumentNullException("value");
}
if (value.Length == 0)
{
return string.Empty;
}
if (upperCase)
{
if (upperHexBytes != null)
{
return ToHexStringFast(value, upperHexBytes);
}
if (value.Length > AllocateThreshold)
{
return ToHexStringFast(value, UpperHexBytes);
}
return ToHexStringSlow(value, UpperHexChars);
}
if (lowerHexBytes != null)
{
return ToHexStringFast(value, lowerHexBytes);
}
if (value.Length > AllocateThreshold)
{
return ToHexStringFast(value, LowerHexBytes);
}
return ToHexStringSlow(value, LowerhexChars);
}
private static string ToHexStringSlow(byte[] value, string hexChars)
{
var hex = new char[value.Length * 2];
int j = 0;
for (var i = 0; i < value.Length; i++)
{
var b = value[i];
hex[j++] = hexChars[b >> 4];
hex[j++] = hexChars[b & 15];
}
return new string(hex);
}
private static string ToHexStringFast(byte[] value, string[] hexBytes)
{
var hex = new char[value.Length * 2];
int j = 0;
for (var i = 0; i < value.Length; i++)
{
var s = hexBytes[value[i]];
hex[j++] = s[0];
hex[j++] = s[1];
}
return new string(hex);
}
private static string[] UpperHexBytes
{
get
{
return (upperHexBytes ?? (upperHexBytes = new[] {
"00", "01", "02", "03", "04", "05", "06", "07", "08", "09", "0A", "0B", "0C", "0D", "0E", "0F",
"10", "11", "12", "13", "14", "15", "16", "17", "18", "19", "1A", "1B", "1C", "1D", "1E", "1F",
"20", "21", "22", "23", "24", "25", "26", "27", "28", "29", "2A", "2B", "2C", "2D", "2E", "2F",
"30", "31", "32", "33", "34", "35", "36", "37", "38", "39", "3A", "3B", "3C", "3D", "3E", "3F",
"40", "41", "42", "43", "44", "45", "46", "47", "48", "49", "4A", "4B", "4C", "4D", "4E", "4F",
"50", "51", "52", "53", "54", "55", "56", "57", "58", "59", "5A", "5B", "5C", "5D", "5E", "5F",
"60", "61", "62", "63", "64", "65", "66", "67", "68", "69", "6A", "6B", "6C", "6D", "6E", "6F",
"70", "71", "72", "73", "74", "75", "76", "77", "78", "79", "7A", "7B", "7C", "7D", "7E", "7F",
"80", "81", "82", "83", "84", "85", "86", "87", "88", "89", "8A", "8B", "8C", "8D", "8E", "8F",
"90", "91", "92", "93", "94", "95", "96", "97", "98", "99", "9A", "9B", "9C", "9D", "9E", "9F",
"A0", "A1", "A2", "A3", "A4", "A5", "A6", "A7", "A8", "A9", "AA", "AB", "AC", "AD", "AE", "AF",
"B0", "B1", "B2", "B3", "B4", "B5", "B6", "B7", "B8", "B9", "BA", "BB", "BC", "BD", "BE", "BF",
"C0", "C1", "C2", "C3", "C4", "C5", "C6", "C7", "C8", "C9", "CA", "CB", "CC", "CD", "CE", "CF",
"D0", "D1", "D2", "D3", "D4", "D5", "D6", "D7", "D8", "D9", "DA", "DB", "DC", "DD", "DE", "DF",
"E0", "E1", "E2", "E3", "E4", "E5", "E6", "E7", "E8", "E9", "EA", "EB", "EC", "ED", "EE", "EF",
"F0", "F1", "F2", "F3", "F4", "F5", "F6", "F7", "F8", "F9", "FA", "FB", "FC", "FD", "FE", "FF" }));
}
}
private static string[] LowerHexBytes
{
get
{
return (lowerHexBytes ?? (lowerHexBytes = new[] {
"00", "01", "02", "03", "04", "05", "06", "07", "08", "09", "0a", "0b", "0c", "0d", "0e", "0f",
"10", "11", "12", "13", "14", "15", "16", "17", "18", "19", "1a", "1b", "1c", "1d", "1e", "1f",
"20", "21", "22", "23", "24", "25", "26", "27", "28", "29", "2a", "2b", "2c", "2d", "2e", "2f",
"30", "31", "32", "33", "34", "35", "36", "37", "38", "39", "3a", "3b", "3c", "3d", "3e", "3f",
"40", "41", "42", "43", "44", "45", "46", "47", "48", "49", "4a", "4b", "4c", "4d", "4e", "4f",
"50", "51", "52", "53", "54", "55", "56", "57", "58", "59", "5a", "5b", "5c", "5d", "5e", "5f",
"60", "61", "62", "63", "64", "65", "66", "67", "68", "69", "6a", "6b", "6c", "6d", "6e", "6f",
"70", "71", "72", "73", "74", "75", "76", "77", "78", "79", "7a", "7b", "7c", "7d", "7e", "7f",
"80", "81", "82", "83", "84", "85", "86", "87", "88", "89", "8a", "8b", "8c", "8d", "8e", "8f",
"90", "91", "92", "93", "94", "95", "96", "97", "98", "99", "9a", "9b", "9c", "9d", "9e", "9f",
"a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7", "a8", "a9", "aa", "ab", "ac", "ad", "ae", "af",
"b0", "b1", "b2", "b3", "b4", "b5", "b6", "b7", "b8", "b9", "ba", "bb", "bc", "bd", "be", "bf",
"c0", "c1", "c2", "c3", "c4", "c5", "c6", "c7", "c8", "c9", "ca", "cb", "cc", "cd", "ce", "cf",
"d0", "d1", "d2", "d3", "d4", "d5", "d6", "d7", "d8", "d9", "da", "db", "dc", "dd", "de", "df",
"e0", "e1", "e2", "e3", "e4", "e5", "e6", "e7", "e8", "e9", "ea", "eb", "ec", "ed", "ee", "ef",
"f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", "f8", "f9", "fa", "fb", "fc", "fd", "fe", "ff" }));
}
}
}
你必须知道以字节表示的字符串的编码，但是你可以说System.Text.UTF8Encoding.GetString(字节)或System.Text.ASCIIEncoding.GetString(字节)。(我是根据记忆做的，所以API可能不完全正确，但它非常接近。)
第二个问题的答案，请看这个问题。
非常快速的扩展方法(带反转):
public static class ExtensionMethods {
public static string ToHex(this byte[] data) {
return ToHex(data, "");
}
public static string ToHex(this byte[] data, string prefix) {
char[] lookup = new char[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
int i = 0, p = prefix.Length, l = data.Length;
char[] c = new char[l * 2 + p];
byte d;
for(; i < p; ++i) c[i] = prefix[i];
i = -1;
--l;
--p;
while(i < l) {
d = data[++i];
c[++p] = lookup[d >> 4];
c[++p] = lookup[d & 0xF];
}
return new string(c, 0, c.Length);
}
public static byte[] FromHex(this string str) {
return FromHex(str, 0, 0, 0);
}
public static byte[] FromHex(this string str, int offset, int step) {
return FromHex(str, offset, step, 0);
}
public static byte[] FromHex(this string str, int offset, int step, int tail) {
byte[] b = new byte[(str.Length - offset - tail + step) / (2 + step)];
byte c1, c2;
int l = str.Length - tail;
int s = step + 1;
for(int y = 0, x = offset; x < l; ++y, x += s) {
c1 = (byte)str[x];
if(c1 > 0x60) c1 -= 0x57;
else if(c1 > 0x40) c1 -= 0x37;
else c1 -= 0x30;
c2 = (byte)str[++x];
if(c2 > 0x60) c2 -= 0x57;
else if(c2 > 0x40) c2 -= 0x37;
else c2 -= 0x30;
b[y] = (byte)((c1 << 4) + c2);
}
return b;
}
}
在上面的速度测试中击败所有其他人:
=== Long string test BitConvertReplace calculation Time Elapsed 2415 ms StringBuilder calculation Time Elapsed 5668 ms LinqConcat calculation Time Elapsed 11826 ms LinqJoin calculation Time Elapsed 9323 ms LinqAgg calculation Time Elapsed 7444 ms ToHexTable calculation Time Elapsed 1028 ms ToHexAcidzombie calculation Time Elapsed 1035 ms ToHexPatrick calculation Time Elapsed 814 ms ToHexKurt calculation Time Elapsed 1604 ms ByteArrayToHexString calculation Time Elapsed 1330 ms === Many string test BitConvertReplace calculation Time Elapsed 2238 ms StringBuilder calculation Time Elapsed 5393 ms LinqConcat calculation Time Elapsed 9043 ms LinqJoin calculation Time Elapsed 9131 ms LinqAgg calculation Time Elapsed 7324 ms ToHexTable calculation Time Elapsed 968 ms ToHexAcidzombie calculation Time Elapsed 969 ms ToHexPatrick calculation Time Elapsed 956 ms ToHexKurt calculation Time Elapsed 1547 ms ByteArrayToHexString calculation Time Elapsed 1277 ms
.Net5.0更新
感谢@antoninkriz的基准比较，我们可以看到Convert。到目前为止，ToHexString是明显的赢家
使用Convert.ToHexString以外的任何方法都是愚蠢的。在我看来，它在可读性、性能和安全性方面明显更胜一筹
剩下的是2012年4月10日之前的数据:
我想我应该尝试比较这里列出的每个方法的速度。我基于这个编写了速度测试代码。
结果是BitConverter+String。替换似乎比大多数其他简单的方法更快。但是可以通过像Nathan Moinvaziri的ByteArrayToHexString或Kurt的ToHex这样的算法来提高速度。
我还发现了一个有趣的字符串。连接和串。对于长字符串，Join比StringBuilder实现慢得多，但对于较短的数组也类似。可能是由于在较长的字符串上扩展StringBuilder，所以设置初始大小应该消除这种差异。
Took each bit of code from an answer here: BitConvertRep = Answer by Guffa, BitConverter and String.Replace (I'd recommend for most cases, [edit:] where you can't use Convert.ToHexString) StringBuilder = Answer by Quintin Robinson, foreach char StringBuilder.Append LinqConcat = Answer by Michael Buen, string.Concat of Linq built array LinqJoin = Answer by mloskot, string.Join of Linq built array LinqAgg = Answer by Matthew Whited, IEnumerable.Aggregate with StringBuilder ToHex = Answer by Kurt, sets chars in an array, using byte values to get hex ByteArrayToHexString = Answer by Nathan Moinvaziri, approx same speed as the ToHex above, and is probably easier to read (I'd recommend for speed, [edit:] where you can't use Convert.ToHexString) ToHexFromTable = Linked in answer by Nathan Moinvaziri, for me this is near the same speed as the above 2 but requires an array of 256 strings to always exist
With: LONG_STRING_LENGTH = 1000 * 1024; BitConvertRep calculation Time Elapsed 27,202 ms (fastest built in/simple) StringBuilder calculation Time Elapsed 75,723 ms (StringBuilder no reallocate) LinqConcat calculation Time Elapsed 182,094 ms LinqJoin calculation Time Elapsed 181,142 ms LinqAgg calculation Time Elapsed 93,087 ms (StringBuilder with reallocating) ToHex calculation Time Elapsed 19,167 ms (fastest) With: LONG_STRING_LENGTH = 100 * 1024;, Similar results BitConvertReplace calculation Time Elapsed 3431 ms StringBuilder calculation Time Elapsed 8289 ms LinqConcat calculation Time Elapsed 21512 ms LinqJoin calculation Time Elapsed 19433 ms LinqAgg calculation Time Elapsed 9230 ms ToHex calculation Time Elapsed 1976 ms With: int MANY_STRING_COUNT = 1000; int MANY_STRING_LENGTH = 1024; (Same byte count as first test but in different arrays) BitConvertReplace calculation Time Elapsed 25,680 ms StringBuilder calculation Time Elapsed 78,411 ms LinqConcat calculation Time Elapsed 101,233 ms LinqJoin calculation Time Elapsed 99,311 ms LinqAgg calculation Time Elapsed 84,660 ms ToHex calculation Time Elapsed 18,221 ms With: int MANY_STRING_COUNT = 2000; int MANY_STRING_LENGTH = 20; BitConvertReplace calculation Time Elapsed 1347 ms StringBuilder calculation Time Elapsed 3234 ms LinqConcat calculation Time Elapsed 5013 ms LinqJoin calculation Time Elapsed 4826 ms LinqAgg calculation Time Elapsed 3589 ms ToHex calculation Time Elapsed 772 ms
我使用的测试代码:
void Main()
{
int LONG_STRING_LENGTH = 100 * 1024;
int MANY_STRING_COUNT = 1024;
int MANY_STRING_LENGTH = 100;
var source = GetRandomBytes(LONG_STRING_LENGTH);
List<byte[]> manyString = new List<byte[]>(MANY_STRING_COUNT);
for (int i = 0; i < MANY_STRING_COUNT; ++i)
{
manyString.Add(GetRandomBytes(MANY_STRING_LENGTH));
}
var algorithms = new Dictionary<string,Func<byte[], string>>();
algorithms["BitConvertReplace"] = BitConv;
algorithms["StringBuilder"] = StringBuilderTest;
algorithms["LinqConcat"] = LinqConcat;
algorithms["LinqJoin"] = LinqJoin;
algorithms["LinqAgg"] = LinqAgg;
algorithms["ToHex"] = ToHex;
algorithms["ByteArrayToHexString"] = ByteArrayToHexString;
Console.WriteLine(" === Long string test");
foreach (var pair in algorithms) {
TimeAction(pair.Key + " calculation", 500, () =>
{
pair.Value(source);
});
}
Console.WriteLine(" === Many string test");
foreach (var pair in algorithms) {
TimeAction(pair.Key + " calculation", 500, () =>
{
foreach (var str in manyString)
{
pair.Value(str);
}
});
}
}
// Define other methods and classes here
static void TimeAction(string description, int iterations, Action func) {
var watch = new Stopwatch();
watch.Start();
for (int i = 0; i < iterations; i++) {
func();
}
watch.Stop();
Console.Write(description);
Console.WriteLine(" Time Elapsed {0} ms", watch.ElapsedMilliseconds);
}
//static byte[] GetRandomBytes(int count) {
// var bytes = new byte[count];
// (new Random()).NextBytes(bytes);
// return bytes;
//}
static Random rand = new Random();
static byte[] GetRandomBytes(int count) {
var bytes = new byte[count];
rand.NextBytes(bytes);
return bytes;
}
static string BitConv(byte[] data)
{
return BitConverter.ToString(data).Replace("-", string.Empty);
}
static string StringBuilderTest(byte[] data)
{
StringBuilder sb = new StringBuilder(data.Length*2);
foreach (byte b in data)
sb.Append(b.ToString("X2"));
return sb.ToString();
}
static string LinqConcat(byte[] data)
{
return string.Concat(data.Select(b => b.ToString("X2")).ToArray());
}
static string LinqJoin(byte[] data)
{
return string.Join("",
data.Select(
bin => bin.ToString("X2")
).ToArray());
}
static string LinqAgg(byte[] data)
{
return data.Aggregate(new StringBuilder(),
(sb,v)=>sb.Append(v.ToString("X2"))
).ToString();
}
static string ToHex(byte[] bytes)
{
char[] c = new char[bytes.Length * 2];
byte b;
for(int bx = 0, cx = 0; bx < bytes.Length; ++bx, ++cx)
{
b = ((byte)(bytes[bx] >> 4));
c[cx] = (char)(b > 9 ? b - 10 + 'A' : b + '0');
b = ((byte)(bytes[bx] & 0x0F));
c[++cx] = (char)(b > 9 ? b - 10 + 'A' : b + '0');
}
return new string(c);
}
public static string ByteArrayToHexString(byte[] Bytes)
{
StringBuilder Result = new StringBuilder(Bytes.Length*2);
string HexAlphabet = "0123456789ABCDEF";
foreach (byte B in Bytes)
{
Result.Append(HexAlphabet[(int)(B >> 4)]);
Result.Append(HexAlphabet[(int)(B & 0xF)]);
}
return Result.ToString();
}
还有一个类似过程的答案，我还没有比较我们的结果。
我不经常把字节转换成十六进制所以我不知道有没有更好的方法，但这里有一种方法。
StringBuilder sb = new StringBuilder();
foreach (byte b in myByteArray)
sb.Append(b.ToString("X2"));
string hexString = sb.ToString();
推荐文章
- 实体框架核心:在上一个操作完成之前，在此上下文中开始的第二个操作
- 如何为构造函数定制Visual Studio的私有字段生成快捷方式?
- 如何使用JSON确保字符串是有效的JSON。网
- Printf与std::字符串?
- AppSettings从.config文件中获取值
- 通过HttpClient向REST API发布一个空体
- 如何检查IEnumerable是否为空或空?
- 不区分大小写的“in”
- 自动化invokerrequired代码模式
- 我如何得到一个字符串的前n个字符而不检查大小或出界?
- 在c#代码中设置WPF文本框的背景颜色
- 在c#中，什么是单子?
- 如何在PHP中截断字符串最接近于一定数量的字符?
- c#和Java中的泛型有什么不同?和模板在c++ ?
- c#线程安全快速(est)计数器
