How to convert color to hexadecimal in php-PHP Problem-php.cn

php method to convert colors to hexadecimal: first create a PHP sample file; then use the "function RGBToHex($rgb){...}" method to convert RGB colors to hexadecimal colors That’s it.

How to convert color to hexadecimal in php

The operating environment of this article: Windows7 system, PHP7.1 version, DELL G3 computer

Hexadecimal color and How to convert RGB color values to each other

The hexadecimal color value is usually expressed as #FFFFFF, and currently it is also reduced to #FFF, provided that the two digits must be the same, such as #FEFEFE. It cannot be reduced. The RGB color format is composed of three groups of numbers from 0 to 255, which represent the color values of red, green, and blue respectively.

So, converting hexadecimal to RGB color values is actually to convert the two digits after the # sign into decimal as one unit.

The code is as follows:

/** * 将16进制颜色转换为RGB * author www.jb51.net */ function hex2rgb($hexColor){ $color=str_replace('#','',$hexColor); if (strlen($color)> 3){ $rgb=array( 'r'=>hexdec(substr($color,0,2)), 'g'=>hexdec(substr($color,2,2)), 'b'=>hexdec(substr($color,4,2)) ); }else{ $r=substr($color,0,1). substr($color,0,1); $g=substr($color,1,1). substr($color,1,1); $b=substr($color,2,1). substr($color,2,1); $rgb=array( 'r'=>hexdec($r), 'g'=>hexdec($g), 'b'=>hexdec($b) ); } return $rgb; }

Copy after login

Another way of writing

/** * 十六进制转RGB * @param string $color 16进制颜色值 * @return array */ public static function hex2rgb($color) { $hexColor = str_replace('#', '', $color); $lens = strlen($hexColor); if ($lens != 3 && $lens != 6) { return false; } $newcolor = ''; if ($lens == 3) { for ($i = 0; $i < $lens; $i++) { $newcolor .= $hexColor[$i] . $hexColor[$i]; } } else { $newcolor = $hexColor; } $hex = str_split($newcolor, 2); $rgb = []; foreach ($hex as $key => $vls) { $rgb[] = hexdec($vls); } return $rgb; }

Copy after login

[Recommended learning:PHP video tutorial]

RGB color and hexadecimal color conversion

/** * RGB转 十六进制 * @param $rgb RGB颜色的字符串 如：rgb(255,255,255); * @return string 十六进制颜色值 如：#FFFFFF */ function RGBToHex($rgb){ $regexp = "/^rgb\(([0-9]{0,3})\,\s*([0-9]{0,3})\,\s*([0-9]{0,3})\)/"; $re = preg_match($regexp, $rgb, $match); $re = array_shift($match); $hexColor = "#"; $hex = array('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'); for ($i = 0; $i < 3; $i++) { $r = null; $c = $match[$i]; $hexAr = array(); while ($c > 16) { $r = $c % 16; $c = ($c / 16) >> 0; array_push($hexAr, $hex[$r]); } array_push($hexAr, $hex[$c]); $ret = array_reverse($hexAr); $item = implode('', $ret); $item = str_pad($item, 2, '0', STR_PAD_LEFT); $hexColor .= $item; } return $hexColor; } /** * 十六进制 转 RGB */ function hex2rgb($hexColor) { $color = str_replace('#', '', $hexColor); if (strlen($color) > 3) { $rgb = array( 'r' => hexdec(substr($color, 0, 2)), 'g' => hexdec(substr($color, 2, 2)), 'b' => hexdec(substr($color, 4, 2)) ); } else { $color = $hexColor; $r = substr($color, 0, 1) . substr($color, 0, 1); $g = substr($color, 1, 1) . substr($color, 1, 1); $b = substr($color, 2, 1) . substr($color, 2, 1); $rgb = array( 'r' => hexdec($r), 'g' => hexdec($g), 'b' => hexdec($b) ); } return $rgb; }

Copy after login

The above is the detailed content of How to convert color to hexadecimal in php. For more information, please follow other related articles on the PHP Chinese website!