bin2hexDescriptionbin2hex() converts a string of ASCII characters to their corresponding hexadecimal values. Note that any value passed to the function is converted to an ASCII string (if possible). The string can be converted back using pack() . See the examples. ExampleExample 1188. Demonstrate how bin2hex() converts a string <pre> <?php $string = "I'm a lumberjack and I'm ok...\n"; // Convert a string to its hex representation $hex_string = bin2hex($string); echo $hex_string, "\n"; // Convert the string back to binary echo pack('H*', $hex_string); echo "\n"; echo "Here is a character-by-character breakdown of how the hex values correspond with character values:\n\n"; // Show more clearly how bin2hex() converts strings // Loop through the converted string two characters at a time for ($ndx = 0; $ndx < strlen($hex_string); $ndx += 2) { // Grab the two hex vales that represent a single character $hex_chunk = $hex_string[$ndx].$hex_string[$ndx+1]; // Show each chunk of the string, along with the character it represents printf("Hex: %s Char: %s\n", $hex_chunk, pack('H2', $hex_chunk)); } ?> </pre> Output: <pre> 49276d2061206c756d6265726a61636b20616e642049276d206f6b2e2e2e0a I'm a lumberjack and I'm ok... Here is a character-by-character breakdown of how the hex values correspond with character values: Hex: 49 Char: I Hex: 27 Char: ' Hex: 6d Char: m Hex: 20 Char: Hex: 61 Char: a Hex: 20 Char: Hex: 6c Char: l Hex: 75 Char: u Hex: 6d Char: m Hex: 62 Char: b Hex: 65 Char: e Hex: 72 Char: r Hex: 6a Char: j Hex: 61 Char: a Hex: 63 Char: c Hex: 6b Char: k Hex: 20 Char: Hex: 61 Char: a Hex: 6e Char: n Hex: 64 Char: d Hex: 20 Char: Hex: 49 Char: I Hex: 27 Char: ' Hex: 6d Char: m Hex: 20 Char: Hex: 6f Char: o Hex: 6b Char: k Hex: 2e Char: . Hex: 2e Char: . Hex: 2e Char: . Hex: 0a Char: </pre> Example 1189. Show how bin2hex() deals with non-character data <pre> <?php // Show how bin2hex() handles non-strings echo "bin2hex('1') returns: " . bin2hex('1') . "\n"; // It converts non-character data to an ASCII string echo "bin2hex(1) returns: " . bin2hex(1) . "\n"; // Can you tell the difference? // To make bin2hex() show the hex representation of 1, use an octal escape sequence echo 'bin2hex("\1") returns: ' . bin2hex("\1") . "\n"; // Try converting a character outside the range of the ASCII character table echo 'bin2hex("\400") returns: ' . bin2hex("\400") . "\n"; ?> </pre> Output <pre> bin2hex('1') returns: 31 bin2hex(1) returns: 31 bin2hex("\1") returns: 01 bin2hex("\400") returns: 00 </pre>
PHP Functions Essential Reference. Copyright © 2002 by New Riders Publishing
(Authors: Zak Greant, Graeme Merrall, Torben Wilson, Brett Michlitsch).
This material may be distributed only subject to the terms and conditions set forth
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The authors of this book have elected not to choose any options under the OPL. This online book was obtained
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