実際に問題-次のコードは機能しません：
$inx = '50'; $str = "\x".$inx; $str .= "\x51"; var_dump($str); // \x50Q
解析すると、このようなコードが機能することがわかりました。
$str = "\x50"; $str .= "\x51"; var_dump($str); // PQ
また、単一引用符で囲まれたコードはまったく機能しません。 シーケンスはまったく解釈されません。
$str = '\x50'; $str .= '\x51'; var_dump($str); // \x50\x51
問題の声明
問題は次のように定式化できます。文字がフラグメントで構成されているタイプ「\ xnn」の動的に形成されたシーケンスを含む文字列の正しい解釈が必要です。
この場合、シンボリックオブジェクトの連結と解釈という2つの操作が実行されます。 そして、それらは厳密な順序で実行されます。 まず、シンボリックオブジェクトの解釈が実行され、次に連結が実行されますが、その逆は実行されません。
したがって、最初の例では、シーケンスの暗号化された文字の1つがフラグメントに分割されます。
このような行は、PHPインタープリターの変換コマンドではなくなりました。
解決策
最初にphpに文字を接着させてから解釈に失敗したため、文字列をそのまま取得し、非解釈シーケンスを既製の文字に置き換えようとします。
タイプ "\ xnn"のシーケンスを文字に変換するための組み込み関数または既製関数を検索しても、明確な結果は得られませんでした。 「彼は見た目が悪いと言っている」（V. Tsoi）。 その結果、この問題はstrtr（）関数を使用して解決されました。 ここでは、解釈不能なシーケンス「\ x50」は、変換可能な「\ x50」に置き換えられます。 違いは引用符のみです。
「\ xnn」などの文字オブジェクトと呼び出しのための既製の関数を次に示します。
function str2escape($string) { $sym_tbl = array( '\x00' => "\x00", '\x01' => "\x01", '\x02' => "\x02", '\x03' => "\x03", '\x04' => "\x04", '\x05' => "\x05", '\x06' => "\x06", '\x07' => "\x07", '\x08' => "\x08", '\x09' => "\x09", '\x0a' => "\x0a", '\x0b' => "\x0b", '\x0c' => "\x0c", '\x0d' => "\x0d", '\x0e' => "\x0e", '\x0f' => "\x0f", '\x11' => "\x11", '\x12' => "\x12", '\x13' => "\x13", '\x14' => "\x14", '\x15' => "\x15", '\x16' => "\x16", '\x17' => "\x17", '\x18' => "\x18", '\x19' => "\x19", '\x1a' => "\x1a", '\x1b' => "\x1b", '\x1c' => "\x1c", '\x1d' => "\x1d", '\x1e' => "\x1e", '\x1f' => "\x1f", '\x21' => "\x21", '\x22' => "\x22", '\x23' => "\x23", '\x24' => "\x24", '\x25' => "\x25", '\x26' => "\x26", '\x27' => "\x27", '\x28' => "\x28", '\x29' => "\x29", '\x2a' => "\x2a", '\x2b' => "\x2b", '\x2c' => "\x2c", '\x2d' => "\x2d", '\x2e' => "\x2e", '\x2f' => "\x2f", '\x31' => "\x31", '\x32' => "\x32", '\x33' => "\x33", '\x34' => "\x34", '\x35' => "\x35", '\x36' => "\x36", '\x37' => "\x37", '\x38' => "\x38", '\x39' => "\x39", '\x3a' => "\x3a", '\x3b' => "\x3b", '\x3c' => "\x3c", '\x3d' => "\x3d", '\x3e' => "\x3e", '\x3f' => "\x3f", '\x41' => "\x41", '\x42' => "\x42", '\x43' => "\x43", '\x44' => "\x44", '\x45' => "\x45", '\x46' => "\x46", '\x47' => "\x47", '\x48' => "\x48", '\x49' => "\x49", '\x4a' => "\x4a", '\x4b' => "\x4b", '\x4c' => "\x4c", '\x4d' => "\x4d", '\x4e' => "\x4e", '\x4f' => "\x4f", '\x51' => "\x51", '\x52' => "\x52", '\x53' => "\x53", '\x54' => "\x54", '\x55' => "\x55", '\x56' => "\x56", '\x57' => "\x57", '\x58' => "\x58", '\x59' => "\x59", '\x5a' => "\x5a", '\x5b' => "\x5b", '\x5c' => "\x5c", '\x5d' => "\x5d", '\x5e' => "\x5e", '\x5f' => "\x5f", '\x61' => "\x61", '\x62' => "\x62", '\x63' => "\x63", '\x64' => "\x64", '\x65' => "\x65", '\x66' => "\x66", '\x67' => "\x67", '\x68' => "\x68", '\x69' => "\x69", '\x6a' => "\x6a", '\x6b' => "\x6b", '\x6c' => "\x6c", '\x6d' => "\x6d", '\x6e' => "\x6e", '\x6f' => "\x6f", '\x71' => "\x71", '\x72' => "\x72", '\x73' => "\x73", '\x74' => "\x74", '\x75' => "\x75", '\x76' => "\x76", '\x77' => "\x77", '\x78' => "\x78", '\x79' => "\x79", '\x7a' => "\x7a", '\x7b' => "\x7b", '\x7c' => "\x7c", '\x7d' => "\x7d", '\x7e' => "\x7e", '\x7f' => "\x7f", '\x81' => "\x81", '\x82' => "\x82", '\x83' => "\x83", '\x84' => "\x84", '\x85' => "\x85", '\x86' => "\x86", '\x87' => "\x87", '\x88' => "\x88", '\x89' => "\x89", '\x8a' => "\x8a", '\x8b' => "\x8b", '\x8c' => "\x8c", '\x8d' => "\x8d", '\x8e' => "\x8e", '\x8f' => "\x8f", '\x91' => "\x91", '\x92' => "\x92", '\x93' => "\x93", '\x94' => "\x94", '\x95' => "\x95", '\x96' => "\x96", '\x97' => "\x97", '\x98' => "\x98", '\x99' => "\x99", '\x9a' => "\x9a", '\x9b' => "\x9b", '\x9c' => "\x9c", '\x9d' => "\x9d", '\x9e' => "\x9e", '\x9f' => "\x9f", '\xa1' => "\xa1", '\xa2' => "\xa2", '\xa3' => "\xa3", '\xa4' => "\xa4", '\xa5' => "\xa5", '\xa6' => "\xa6", '\xa7' => "\xa7", '\xa8' => "\xa8", '\xa9' => "\xa9", '\xaa' => "\xaa", '\xab' => "\xab", '\xac' => "\xac", '\xad' => "\xad", '\xae' => "\xae", '\xaf' => "\xaf", '\xb1' => "\xb1", '\xb2' => "\xb2", '\xb3' => "\xb3", '\xb4' => "\xb4", '\xb5' => "\xb5", '\xb6' => "\xb6", '\xb7' => "\xb7", '\xb8' => "\xb8", '\xb9' => "\xb9", '\xba' => "\xba", '\xbb' => "\xbb", '\xbc' => "\xbc", '\xbd' => "\xbd", '\xbe' => "\xbe", '\xbf' => "\xbf", '\xc1' => "\xc1", '\xc2' => "\xc2", '\xc3' => "\xc3", '\xc4' => "\xc4", '\xc5' => "\xc5", '\xc6' => "\xc6", '\xc7' => "\xc7", '\xc8' => "\xc8", '\xc9' => "\xc9", '\xca' => "\xca", '\xcb' => "\xcb", '\xcc' => "\xcc", '\xcd' => "\xcd", '\xce' => "\xce", '\xcf' => "\xcf", '\xd1' => "\xd1", '\xd2' => "\xd2", '\xd3' => "\xd3", '\xd4' => "\xd4", '\xd5' => "\xd5", '\xd6' => "\xd6", '\xd7' => "\xd7", '\xd8' => "\xd8", '\xd9' => "\xd9", '\xda' => "\xda", '\xdb' => "\xdb", '\xdc' => "\xdc", '\xdd' => "\xdd", '\xde' => "\xde", '\xdf' => "\xdf", '\xe1' => "\xe1", '\xe2' => "\xe2", '\xe3' => "\xe3", '\xe4' => "\xe4", '\xe5' => "\xe5", '\xe6' => "\xe6", '\xe7' => "\xe7", '\xe8' => "\xe8", '\xe9' => "\xe9", '\xea' => "\xea", '\xeb' => "\xeb", '\xec' => "\xec", '\xed' => "\xed", '\xee' => "\xee", '\xef' => "\xef", '\xf1' => "\xf1", '\xf2' => "\xf2", '\xf3' => "\xf3", '\xf4' => "\xf4", '\xf5' => "\xf5", '\xf6' => "\xf6", '\xf7' => "\xf7", '\xf8' => "\xf8", '\xf9' => "\xf9", '\xfa' => "\xfa", '\xfb' => "\xfb", '\xfc' => "\xfc", '\xfd' => "\xfd", '\xfe' => "\xfe", '\xff' => "\xff", ); return strtr($string, $sym_tbl); } // : $str = str2escape($str);
これですべてが正常になりました。
$inx = '50'; $str = "\x".$inx; $str .= "\x51"; var_dump(str2escape($str)); // PQ
Habra-Mikhailは、独自の機能を使用せずにオプションを提案しました
$inx = '50'; $str = chr(hexdec($inx)); $str .= "\x51"; var_dump($str); // PQ
原因と解決策の検索にはある程度の時間がかかりました。私が旅した道は、将来同様のタスクに遭遇するすべての人がそれをより早く理解するのに役立つと思います。