PHP是否有更好的方法从8位字符串表示中获取ascii值?

时间:2012-12-16 14:10:45

标签: php bits chr

这就是我目前正在做的事情。我使用php chr函数来获取该字符的8位字符串表示的相应ascii数。

在我看来,有一种更好的方法可以做到这一点。是否有我失踪的PHP功能。为udp / dns编程做一些位工作。我知道我应该使用差异语言,稍后我会撬开端口,但是现在有什么想法吗?

function get_ascii_character_from_bits($bits){
$binary_codes=array(
'00000000'=>0,
'00000001'=>1,
'00000010'=>2,
'00000011'=>3,
'00000100'=>4,
'00000101'=>5,
'00000110'=>6,
'00000111'=>7,
'00001000'=>8,
'00001001'=>9,
'00001010'=>10,
'00001011'=>11,
'00001100'=>12,
'00001101'=>13,
'00001110'=>14,
'00001111'=>15,
'00010000'=>16,
'00010001'=>17,
'00010010'=>18,
'00010011'=>19,
'00010100'=>20,
'00010101'=>21,
'00010110'=>22,
'00010111'=>23,
'00011000'=>24,
'00011001'=>25,
'00011010'=>26,
'00011011'=>27,
'00011100'=>28,
'00011101'=>29,
'00011110'=>30,
'00011111'=>31,
'00100000'=>32,
'00100001'=>33,
'00100010'=>34,
'00100011'=>35,
'00100100'=>36,
'00100101'=>37,
'00100110'=>38,
'00100111'=>39,
'00101000'=>40,
'00101001'=>41,
'00101010'=>42,
'00101011'=>43,
'00101100'=>44,
'00101101'=>45,
'00101110'=>46,
'00101111'=>47,
'00110000'=>48,
'00110001'=>49,
'00110010'=>50,
'00110011'=>51,
'00110100'=>52,
'00110101'=>53,
'00110110'=>54,
'00110111'=>55,
'00111000'=>56,
'00111001'=>57,
'00111010'=>58,
'00111011'=>59,
'00111100'=>60,
'00111101'=>61,
'00111110'=>62,
'00111111'=>63,
'01000000'=>64,
'01000001'=>65,
'01000010'=>66,
'01000011'=>67,
'01000100'=>68,
'01000101'=>69,
'01000110'=>70,
'01000111'=>71,
'01001000'=>72,
'01001001'=>73,
'01001010'=>74,
'01001011'=>75,
'01001100'=>76,
'01001101'=>77,
'01001110'=>78,
'01001111'=>79,
'01010000'=>80,
'01010001'=>81,
'01010010'=>82,
'01010011'=>83,
'01010100'=>84,
'01010101'=>85,
'01010110'=>86,
'01010111'=>87,
'01011000'=>88,
'01011001'=>89,
'01011010'=>90,
'01011011'=>91,
'01011100'=>92,
'01011101'=>93,
'01011110'=>94,
'01011111'=>95,
'01100000'=>96,
'01100001'=>97,
'01100010'=>98,
'01100011'=>99,
'01100100'=>100,
'01100101'=>101,
'01100110'=>102,
'01100111'=>103,
'01101000'=>104,
'01101001'=>105,
'01101010'=>106,
'01101011'=>107,
'01101100'=>108,
'01101101'=>109,
'01101110'=>110,
'01101111'=>111,
'01110000'=>112,
'01110001'=>113,
'01110010'=>114,
'01110011'=>115,
'01110100'=>116,
'01110101'=>117,
'01110110'=>118,
'01110111'=>119,
'01111000'=>120,
'01111001'=>121,
'01111010'=>122,
'01111011'=>123,
'01111100'=>124,
'01111101'=>125,
'01111110'=>126,
'01111111'=>127,
'10000000'=>128,
'10000001'=>129,
'10000010'=>130,
'10000011'=>131,
'10000100'=>132,
'10000101'=>133,
'10000110'=>134,
'10000111'=>135,
'10001000'=>136,
'10001001'=>137,
'10001010'=>138,
'10001011'=>139,
'10001100'=>140,
'10001101'=>141,
'10001110'=>142,
'10001111'=>143,
'10010000'=>144,
'10010001'=>145,
'10010010'=>146,
'10010011'=>147,
'10010100'=>148,
'10010101'=>149,
'10010110'=>150,
'10010111'=>151,
'10011000'=>152,
'10011001'=>153,
'10011010'=>154,
'10011011'=>155,
'10011100'=>156,
'10011101'=>157,
'10011110'=>158,
'10011111'=>159,
'10100000'=>160,
'10100001'=>161,
'10100010'=>162,
'10100011'=>163,
'10100100'=>164,
'10100101'=>165,
'10100110'=>166,
'10100111'=>167,
'10101000'=>168,
'10101001'=>169,
'10101010'=>170,
'10101011'=>171,
'10101100'=>172,
'10101101'=>173,
'10101110'=>174,
'10101111'=>175,
'10110000'=>176,
'10110001'=>177,
'10110010'=>178,
'10110011'=>179,
'10110100'=>180,
'10110101'=>181,
'10110110'=>182,
'10110111'=>183,
'10111000'=>184,
'10111001'=>185,
'10111010'=>186,
'10111011'=>187,
'10111100'=>188,
'10111101'=>189,
'10111110'=>190,
'10111111'=>191,
'11000000'=>192,
'11000001'=>193,
'11000010'=>194,
'11000011'=>195,
'11000100'=>196,
'11000101'=>197,
'11000110'=>198,
'11000111'=>199,
'11001000'=>200,
'11001001'=>201,
'11001010'=>202,
'11001011'=>203,
'11001100'=>204,
'11001101'=>205,
'11001110'=>206,
'11001111'=>207,
'11010000'=>208,
'11010001'=>209,
'11010010'=>210,
'11010011'=>211,
'11010100'=>212,
'11010101'=>213,
'11010110'=>214,
'11010111'=>215,
'11011000'=>216,
'11011001'=>217,
'11011010'=>218,
'11011011'=>219,
'11011100'=>220,
'11011101'=>221,
'11011110'=>222,
'11011111'=>223,
'11100000'=>224,
'11100001'=>225,
'11100010'=>226,
'11100011'=>227,
'11100100'=>228,
'11100101'=>229,
'11100110'=>230,
'11100111'=>231,
'11101000'=>232,
'11101001'=>233,
'11101010'=>234,
'11101011'=>235,
'11101100'=>236,
'11101101'=>237,
'11101110'=>238,
'11101111'=>239,
'11110000'=>240,
'11110001'=>241,
'11110010'=>242,
'11110011'=>243,
'11110100'=>244,
'11110101'=>245,
'11110110'=>246,
'11110111'=>247,
'11111000'=>248,
'11111001'=>249,
'11111010'=>250,
'11111011'=>251,
'11111100'=>252,
'11111101'=>253,
'11111110'=>254,
'11111111'=>255
);
return chr($binary_codes[$bits]);
}

1 个答案:

答案 0 :(得分:3)

我认为你的函数本质上是bindec正在做的事情,接受的输入范围要小得多,并且调用chr

即。你的功能相当于

chr(bindec($bits));

表示0到255之间的输出。