hexdec()

(PHP 4, PHP 5, PHP 7)

十六进制转换为十进制

说明

返回与$hex_string参数所表示的十六进制数等值的的十进制数。hexdec()将一个十六进制字符串转换为十进制数。

hexdec()会忽略它遇到的任意非十六进制的字符。

参数

要转换的十六进制的字符串

返回值

$hex_string十进制的表示

更新日志

范例

Example #1hexdec()例子

参见

• dechex() 十进制转换为十六进制
• bindec() 二进制转换为十进制
• octdec() 八进制转换为十进制
• base_convert() 在任意进制之间转换数字

Use this function to convert a hexa decimal color code to its RGB equivalent. Unlike many other functions provided here, it will work correctly with hex color short hand notation.
Also, if a proper hexa decimal color value is given (6 digits), it uses bit wise operations for faster results.
For eg: #FFF and #FFFFFF will produce the same result

OUTPUT:
hex2RGB("#FF0") -> array( red =>255, green => 255, blue => 0)
hex2RGB("#FFFF00) -> Same as above
hex2RGB("#FF0", true) -> 255,255,0
hex2RGB("#FF0", true, ":") -> 255:255:0

Here is other function to transform a MAC Address to decimal: 

Here's my hexdec function for greater numbers using BC Math 

RGB to Hex
Hex to RGB
Function

Output
#FFFFFF =>
 Array{
  red=>255,
  green=>255,
  blue=>255,
  r=>255,
  g=>255,
  b=>255,
  0=>255,
  1=>255,
  2=>255
 }
 
#FFCCEE =>
 Array{
  red=>255,
  green=>204,
  blue=>238,
  r=>255,
  g=>204,
  b=>238,
  0=>255,
  1=>204,
  2=>238
 }
CC22FF =>
 Array{
  red=>204,
  green=>34,
  blue=>255,
  r=>204,
  g=>34,
  b=>255,
  0=>204,
  1=>34,
  2=>255
 }
0 65 255 => #0041FF
255.150.3 => #FF9603
100,100,250 => #6464FA
[EDIT BY danbrown AT php DOT net - Contains multiple bugfixes by (ajim1417 AT gmail DOT com) on 27-JAN-2010: Replaces typo in explode() and updates eregi() calls to preg_match().]

If you want to create or parse signed Hex strings:

Also note that ('0x' . $hexstr + 0) is faster than hexdec()
(Tested on PHP v5.2.17)

Here My version of converting a hex string to a signed decimal value: 

One of my favourite, multi-purpose, bidirectional solution I wrote many years ago: 
function bgr2rgb($cr) { // bidirectional
  return (($cr & 0x0000FF) > 16);
}
Which you might want to use as :
function hex2cr($hex) { // strips any leading characters, like #
  return bgr2rgb(hexdec($hex));
}
function cr2hex($cr) { // the usual HTML format, #rrggbb
  return '#'.str_pad(strtoupper(dechex(bgr2rgb($cr))), 6, '0', STR_PAD_LEFT);
}
And, if like me you tend to mistype function names, the synonym : 
function rgb2bgr($val) { return bgr2rgb($val); }

I wondered long time what is the best way to generate RGB-color from HEX-color, and just now i found the simpliest way!

I hope this will save your time! :)

I made these functions to pack up to 64 ID's into a mysql unsigned bigint.
ID's cannot repeat, must be 
Have fun ;D

The issue I've seen with the existing hex to dec conversion routines is the lack of error-trapping. I stick to the theory that one should try to cover ALL the bases when writing a generalized routine such as this one. I have a varied background that covers a wide variety of design/development languages, on the web as well as desktop apps. As such I've seen multiple formats for writing hex colors.
For example, the color red COULD be written as follows:
#ff0000
&Hff0000
#ff
&Hff
Therefore I have written a function that is case-insensitive and takes into account the chance that different developers have a tendency to format hex colors in different ways.

As you can see, the function "convert_color" accepts a hex # in most acceptable formats and returns an associative array. [success] is set to TRUE if the function succeeds and FALSE if not. The array members [r], [g] and [b] hold the red,green and blue values respectively. If it fails, [error] holds a custom error message.
"strip_chars" is a support function written to remove the unwanted characters from the hex string, and sends the concatenated string back to the calling function. It will accept either a single value or an array of values for the characters to remove.

// Função GET Cor Hexadecima e Retorna em RGB
function hexrgb($hexstr, $rgb) {
 $int = hexdec($hexstr);
 switch($rgb) {
    case "r":
    return 0xFF & $int >> 0x10;
      break;
    case "g":
    return 0xFF & ($int >> 0x8);
      break;
    case "b":
    return 0xFF & $int;
      break;
    default:
    return array(
      "r" => 0xFF & $int >> 0x10,
      "g" => 0xFF & ($int >> 0x8),
      "b" => 0xFF & $int
      );
      break;
  }  
}// END GET Cor Hex => RGB
//Uso
 echo hexrgb("1a2b3c", r); // 26
 echo hexrgb("1a2b3c", g); // 43
 echo hexrgb("1a2b3c", b); // 60
//ou
var_dump(hexrgb("1a2b3c", rgb)); //array(3) { ["r"]=> int(26) ["g"]=> int(43) ["b"]=> int(60) }

After esnhexdec from "rledger at gmail dot com", the esndechex: 

hexdec from 4.1.0 onwards does not show
the same size limitation and therefore
works differently with large numbers than previous php versions.
To obtain the same results, use:
(int) hexdec (...)

hexdec doesn't accept numbers following the period.
What if you have a number like c20.db18? 

Help a hex-stricken string get back to normal: 

function hex2rgb($hex) {
  if ($hex[0]=='#') $hex = substr($hex,1);
  if (strlen($hex)==3){
    $hex = $hex[0].$hex[0].$hex[1].$hex[1].$hex[2].$hex[2];
  }
  $int = hexdec($hex);
  return array("red" => 0xFF & ($int >> 0x10), "green" => 0xFF & ($int >> 0x8), "blue" => 0xFF & $int);
}

This tiny function will return foreground colors (either black or white) in contrast to the color you provide:

This function will return the opposite (negative): 

Here is my version of hex2rgb for web colors to 24bit colors. 

From color to color to ...... to color with fade effect. Good for dynamic bar chart.

Repley.

A handy little function to convert HEX colour codes to "web safe" colours...

Example: color_mkwebsafe('0e5c94');
Produces: 006699
Hope this helps someone out... Happy coding. :-)

I made this for a little phpbb mod. It was used to take the hex value from the database and make a color 20 (in decimal) less, resulting a darker color.
EXAMPLE: #336699 to #1f5285 

Bullet-proof hex-to-rgb colour converter like brian at sagesport dot com wanted, just far fewer code lines. As a bonus, gives you the ability to return as string or array:

Handles 2, 3, and 6 character colour codes with leading # or &H.

This replaces my previous class.
I've added a few more input checks in the rgb2hex function.
Also it returned incorrect hex values for 1-digit values.
color::rgb2hex(array(0,0,0)) would output 000 not 00000. 

It's just a revision to marfastic's ligten_up script, it simply adds/subtracts mod_color to orig_color.
I use it often to adjust tonals rather than brightness only 

Here's another hex2bin variant, works pretty well to me.
function hex2bin($hexdata) {
  
  for ($i=0;$i 0,
    "1" => 1,
    "2" => 2,
    "3" => 3,
    "4" => 4,
    "5" => 5,
    "6" => 6,
    "7" => 7,
    "8" => 8,
    "9" => 9,
    "A" => 10,
    "B" => 11,
    "C" => 12,
    "D" => 13,
    "E" => 14,
    "F" => 15
  );
  $dec = 0;
  for ($i = strlen($hex) - 1, $e = 1; $i >= 0; $i--, $e = bcmul($e, 16)) {
    $factor = $hexdec[$hex[$i]];
    $dec = bcadd($dec, bcmul($factor, $e));
  }
  return $dec;
}

In reply to Amit Yadav's post (hex to binary conversion):
function binfromdec($num) 
{
 $primary = "bit";
 for ($i=1; $i 32766)  return ("Too Large!");
  if ($num & 16384)  $bit15 = 1;
  if ($num & 8192)  $bit14 = 1;
  if ($num & 4096)  $bit13 = 1;
  if ($num & 2048)  $bit12 = 1;
  if ($num & 1024)  $bit11 = 1;
  if ($num & 512)    $bit10 = 1;
  if ($num & 256)    $bit9 = 1;
  if ($num & 128)    $bit8 = 1;
  if ($num & 64)    $bit7 = 1;
  if ($num & 32)    $bit6 = 1;
  if ($num & 16)    $bit5 = 1;
  if ($num & 8)    $bit4 = 1;
  if ($num & 4)    $bit3 = 1;
  if ($num & 2)    $bit2 = 1;
  if ($num & 1)    $bit1 = 1;
  return ("" . $bit15 . $bit14 . $bit13 . $bit12 . $bit11 . $bit10 . $bit9 . $bit8 . $bit7 . $bit6 . $bit5 . $bit4 . $bit3 . $bit2 . $bit1);
}

Here's a short example to convert strings between hex and chars: 

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