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?
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
我想我做了一个更快的字节数组到字符串转换器:
public static class HexTable
{
private static readonly string[] table = BitConverter.ToString(Enumerable.Range(0, 256).Select(x => (byte)x).ToArray()).Split('-');
public static string ToHexTable(byte[] value)
{
StringBuilder sb = new StringBuilder(2 * value.Length);
for (int i = 0; i < value.Length; i++)
sb.Append(table[value[i]]);
return sb.ToString();
}
并且测试设置:
static void Main(string[] args)
{
const int TEST_COUNT = 10000;
const int BUFFER_LENGTH = 100000;
Random random = new Random();
Stopwatch sw = new Stopwatch();
Stopwatch sw2 = new Stopwatch();
byte[] buffer = new byte[BUFFER_LENGTH];
random.NextBytes(buffer);
sw.Start();
for (int j = 0; j < TEST_COUNT; j++)
HexTable.ToHexTable(buffer);
sw.Stop();
sw2.Start();
for (int j = 0; j < TEST_COUNT; j++)
ToHexChar.ToHex(buffer);
sw2.Stop();
Console.WriteLine("Hex Table Elapsed Milliseconds: {0}", sw.ElapsedMilliseconds);
Console.WriteLine("ToHex Elapsed Milliseconds: {0}", sw2.ElapsedMilliseconds);
}
ToHexChar.ToHEx()方法是前面所示的ToHex()方法。
结果如下:
HexTable = 11808 ms ToHEx = 12168ms
它看起来可能没有太大的不同,但它仍然更快:)
其他回答
我想我做了一个更快的字节数组到字符串转换器:
public static class HexTable
{
private static readonly string[] table = BitConverter.ToString(Enumerable.Range(0, 256).Select(x => (byte)x).ToArray()).Split('-');
public static string ToHexTable(byte[] value)
{
StringBuilder sb = new StringBuilder(2 * value.Length);
for (int i = 0; i < value.Length; i++)
sb.Append(table[value[i]]);
return sb.ToString();
}
并且测试设置:
static void Main(string[] args)
{
const int TEST_COUNT = 10000;
const int BUFFER_LENGTH = 100000;
Random random = new Random();
Stopwatch sw = new Stopwatch();
Stopwatch sw2 = new Stopwatch();
byte[] buffer = new byte[BUFFER_LENGTH];
random.NextBytes(buffer);
sw.Start();
for (int j = 0; j < TEST_COUNT; j++)
HexTable.ToHexTable(buffer);
sw.Stop();
sw2.Start();
for (int j = 0; j < TEST_COUNT; j++)
ToHexChar.ToHex(buffer);
sw2.Stop();
Console.WriteLine("Hex Table Elapsed Milliseconds: {0}", sw.ElapsedMilliseconds);
Console.WriteLine("ToHex Elapsed Milliseconds: {0}", sw2.ElapsedMilliseconds);
}
ToHexChar.ToHEx()方法是前面所示的ToHex()方法。
结果如下:
HexTable = 11808 ms ToHEx = 12168ms
它看起来可能没有太大的不同,但它仍然更快:)
有一个内置的方法:
byte[] data = { 1, 2, 4, 8, 16, 32 };
string hex = BitConverter.ToString(data);
结果:01-02-04-08-10-20
如果你想要没有破折号,只需删除它们:
string hex = BitConverter.ToString(data).Replace("-", string.Empty);
结果:010204081020
如果你想要一个更紧凑的表示,你可以使用Base64:
string base64 = Convert.ToBase64String(data);
结果:AQIECBAg
十六进制,Linq-fu:
string.Concat(ba.Select(b => b.ToString("X2")).ToArray())
与时俱进
正如@RubenBartelink所指出的,没有将IEnumerable<string>转换为数组的代码:ba。Select(b => b. tostring ("X2"))在4.0之前不工作,相同的代码现在在4.0上工作。
这段代码…
byte[] ba = { 1, 2, 4, 8, 16, 32 };
string s = string.Concat(ba.Select(b => b.ToString("X2")));
string t = string.Concat(ba.Select(b => b.ToString("X2")).ToArray());
Console.WriteLine (s);
Console.WriteLine (t);
...在。net 4.0之前,输出是:
System.Linq.Enumerable+<CreateSelectIterator>c__Iterator10`2[System.Byte,System.String]
010204081020
在。net 4.0以后,字符串。Concat有一个接受IEnumerable的重载。因此,在4.0版本中,上述代码对于变量s和t将有相同的输出
010204081020
010204081020
4.0之前,ba。Select(b => b.ToString("X2"))将重载(对象arg0), IEnumerable<string>进入适当重载的方式,即(params string[] values),是我们需要将IEnumerable<string>转换为字符串数组。4.0之前,字符串。Concat有10个过载功能,在4.0现在是12个
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
正如其他人所说,这取决于字节数组中值的编码方式。尽管如此,您还是需要非常小心地处理这类事情,否则您可能会尝试转换未被所选编码处理的字节。
Jon Skeet有一篇关于。net中的编码和unicode的好文章。推荐阅读。