[PHP] - 按长度截取字符串(针对UTF-8)
代码是看看规范又抄又改,希望是完美没错...
/********************************************************************* * * Func Name : SubStrEx * * Description : * 按长度截取字符串 * * * Parameters : * $sString[string] : 字符串 * $nLength[int] : 要取长度 * $sDot[string="..."] : 截断符 * $sCharset[string="UTF-8"] : 编码 * * Returns : [bool]保存结果 * *********************************************************************/ function SubStrEx ($sString, $nLength, $sDot = "...", $sCharset = "UTF-8") { if (strlen($sString) <= $nLength) { return $sString; } $sString = str_replace(array("&", "\"", "<", ">"), array("&", "\"", "<", ">"), $sString); $sStrcut = ""; if (strtoupper($sCharset) == "UTF-8") { $nPos = 0; $nWordLen = 0; $noc = 0; // 单字节字符+1,多字节+2(将非单字节字符的长度当做是2[应该是视觉感觉吧]) while ($nPos < strlen($sString)) { $t = ord($sString[$nPos]); if ($t == 9 || $t == 10 || (32 <= $t && $t <= 126)) { $nWordLen = 1; $noc++; } elseif (194 <= $t && $t <= 223) { $nWordLen = 2; $noc += 2; } elseif (224 <= $t && $t <= 239) { $nWordLen = 3; $noc += 2; } elseif (240 <= $t && $t <= 247) { $nWordLen = 4; $noc += 2; } elseif (248 <= $t && $t <= 251) { $nWordLen = 5; $noc += 2; } elseif ($t == 252 || $t == 253) { $nWordLen = 6; $noc += 2; } else { $nWordLen = 0; } $nPos += ($nWordLen > 0) ? $nWordLen : 1; if ($noc >= $nLength) { break; } } if ($noc > $nLength) { $nPos -= $nWordLen; } $sStrcut = substr($sString, 0, $nPos); } else { for ($i = 0; $i < $nLength; $i++) { $sStrcut .= ord($sString[$i]) > 127 ? $sString[$i] . $sString[++ $i] : $sString[$i]; } } $sStrcut = str_replace(array("&", "\"", "<", ">"), array("&", "\"", "<", ">"), $sStrcut); return $sStrcut . $sDot; }
个性签名:做要做好,做到不三不四不如不做。