php字符串处理函数

字符串截取，支持中文和其他编码

/**
+----------------------------------------------------------
* 字符串截取，支持中文和其他编码
+----------------------------------------------------------
* @static
* @access public
+----------------------------------------------------------
* @param string $str 需要转换的字符串
* @param string $start 开始位置
* @param string $length 截取长度
* @param string $charset 编码格式
* @param string $suffix 截断显示字符
+----------------------------------------------------------
* @return string
+----------------------------------------------------------
*/
public static function msubstr($str, $start = 0, $length, $charset = "utf-8", $suffix = true) {
if (function_exists("mb_substr"))
return mb_substr($str, $start, $length, $charset);
elseif (function_exists('iconv_substr')) {
return iconv_substr($str, $start, $length, $charset);
}
$re['utf-8'] = "/[\x01-\x7f]|[\xc2-\xdf][\x80-\xbf]|[\xe0-\xef][\x80-\xbf]{2}|[\xf0-\xff][\x80-\xbf]{3}/";
$re['gb2312'] = "/[\x01-\x7f]|[\xb0-\xf7][\xa0-\xfe]/";
$re['gbk'] = "/[\x01-\x7f]|[\x81-\xfe][\x40-\xfe]/";
$re['big5'] = "/[\x01-\x7f]|[\x81-\xfe]([\x40-\x7e]|\xa1-\xfe])/";
preg_match_all($re[$charset], $str, $match);
$slice = join("", array_slice($match[0], $start, $length));
if ($suffix)
return $slice . "…";
return $slice;
}

去除空白字符[\r\n\t\s]

// 去除空白字符[\r\n\t\s]
public static function trim_str($str)	{
return preg_replace('/[\r\n\t\s]+/','',$str);
}

产生随机字串，可用来自动生成密码 默认长度6位 字母和数字混合

/**
+----------------------------------------------------------
* 产生随机字串，可用来自动生成密码 默认长度6位 字母和数字混合
+----------------------------------------------------------
* @param string $len 长度
* @param string $type 字串类型
* 0 字母 1 数字 其它 混合
* @param string $addChars 额外字符
+----------------------------------------------------------
* @return string
+----------------------------------------------------------
*/
public static function rand_string($len = 6, $type = '', $addChars = '') {
$str = '';
switch ($type) {
case 0 :
$chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz' . $addChars;
break;
case 1 :
$chars = str_repeat('0123456789', 3);
break;
case 2 :
$chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ' . $addChars;
break;
case 3 :
$chars = 'abcdefghijklmnopqrstuvwxyz' . $addChars;
break;
default :
// 默认去掉了容易混淆的字符oOLl和数字01，要添加请使用addChars参数
$chars = 'ABCDEFGHIJKMNPQRSTUVWXYZabcdefghijkmnpqrstuvwxyz23456789' . $addChars;
break;
}
if ($len > 10) { //位数过长重复字符串一定次数
$chars = $type == 1 ? str_repeat($chars, $len) : str_repeat($chars, 5);
}
if ($type != 4) {
$chars = str_shuffle($chars);
$str = substr($chars, 0, $len);
} else {
// 中文随机字
for ($i = 0; $i < $len; $i++) {
$str .= msubstr($chars, floor(mt_rand(0, mb_strlen($chars, 'utf-8') - 1)), 1);
}
}
return $str;
}

格式化数据（防止注入）

//格式化数据（防止注入）
public static function site_addslashes($string, $force = 0) {
!defined('MAGIC_QUOTES_GPC') && define('MAGIC_QUOTES_GPC', get_magic_quotes_gpc());
if (!MAGIC_QUOTES_GPC || $force) {
if (is_array($string)) {
foreach ($string as $key => $val) {
$string[$
3ff0
key] = daddslashes($val, $force);
}
} else {
$string = addslashes($string);
}
}
return $string;
}

防止XSS攻击,用在表单textarea中内容过滤较多

// 防止XSS攻击,用在表单textarea中内容过滤较多
public static function remove_xss($val) {
$val = preg_replace('/([\x00-\x08,\x0b-\x0c,\x0e-\x19])/', '', $val);
$search = 'abcdefghijklmnopqrstuvwxyz';
$search .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
$search .= '1234567890!@#$%^&*()';
$search .= '~`";:?+/={}[]-_|\'\\';
for ($i = 0; $i < strlen($search); $i++) {
$val = preg_replace('/(&#[xX]0{0,8}' . dechex(ord($search[$i])) . ';?)/i', $search[$i], $val); // with a ;
$val = preg_replace('/(�{0,8}' . ord($search[$i]) . ';?)/', $search[$i], $val); // with a ;
}
$ra1 = array(
'javascript',
'vbscript',
'expression',
'applet',
'meta',
'xml',
'blink',
'style',
'script',
'embed',
'object',
'iframe',
'frame',
'frameset',
'ilayer',
'layer',
'bgsound',
'title',
'base'
);
$ra2 = array(
'onabort',
'onactivate',
'onafterprint',
'onafterupdate',
'onbeforeactivate',
'onbeforecopy',
'onbeforecut',
'onbeforedeactivate',
'onbeforeeditfocus',
'onbeforepaste',
'onbeforeprint',
'onbeforeunload',
'onbeforeupdate',
'onblur',
'onbounce',
'oncellchange',
'onchange',
'onclick',
'oncontextmenu',
'oncontrolselect',
'oncopy',
'oncut',
'ondataavailable',
'ondatasetchanged',
'ondatasetcomplete',
'ondblclick',
'ondeactivate',
'ondrag',
'ondragend',
'ondragenter',
'ondragleave',
'ondragover',
'ondragstart',
'ondrop',
'onerror',
'onerrorupdate',
'onfilterchange',
'onfinish',
'onfocus',
'onfocusin',
'onfocusout',
'onhelp',
'onkeydown',
'onkeypress',
'onkeyup',
'onlayoutcomplete',
'onload',
'onlosecapture',
'onmousedown',
'onmouseenter',
'onmouseleave',
'onmousemove',
'onmouseout',
'onmouseover',
'onmouseup',
'onmousewheel',
'onmove',
'onmoveend',
'onmovestart',
'onpaste',
'onpropertychange',
'onreadystatechange',
'onreset',
'onresize',
'onresizeend',
'onresizestart',
'onrowenter',
'onrowexit',
'onrowsdelete',
'onrowsinserted',
'onscroll',
'onselect',
'onselectionchange',
'onselectstart',
'onstart',
'onstop',
'onsubmit',
'onunload'
);
$ra = array_merge($ra1, $ra2);
$found = true; // keep replacing as long as the previous round replaced something
while ($found == true) {
$val_before = $val;
for ($i = 0; $i < sizeof($ra); $i++) {
$pattern = '/';
for ($j = 0; $j < strlen($ra[$i]); $j++) {
if ($j > 0) {
$pattern .= '(';
$pattern .= '(&#[xX]0{0,8}([9ab]);)';
$pattern .= '|';
$pattern .= '|(�{0,8}([9|10|13]);)';
$pattern .= ')*';
}
$pattern .= $ra[$i][$j];
}
$pattern .= '/i';
$replacement = substr($ra[$i], 0, 2) . '<x>' . substr($ra[$i], 2); // add in <> to nerf the tag
$val = preg_replace($pattern, $replacement, $val); // filter out the hex tags
if ($val_before == $val) {
// no replacements were made, so exit the loop
$found = false;
}
}
}
$string = self::safegl($val);
return $string;
}