在對(duì)于字符串的替換上，我們已經(jīng)學(xué)過(guò)了不少的方法。但在做練習(xí)題的時(shí)候，我們會(huì)對(duì)多個(gè)字符串進(jìn)行替換。從方法的實(shí)用性來(lái)說(shuō)，str_replace就非常適合處理多個(gè)字符串的替換問(wèn)題。下面我們就php中str_replace的概念、語(yǔ)法、參數(shù)、返回值進(jìn)行講解，然后帶來(lái)替換的實(shí)例分享。

str_replace() 函數(shù)以其他字符替換字符串中的一些字符（區(qū)分大小寫(xiě)）。

該函數(shù)區(qū)分大小寫(xiě)。請(qǐng)使用 str_ireplace() 函數(shù)執(zhí)行不區(qū)分大小寫(xiě)的搜索。

str_replace(find,replace,string,count)3、參數(shù)

Find、replace、string、count

返回帶有替換值的字符串或數(shù)組。

創(chuàng)建一個(gè)PHP示例文件；然后通過(guò)“tr_replace($vowels, '','Hello World of PHP');”方法替換多個(gè)字符串即可。

echo str_replace(array('m','i'),array('n','z'),'my name is jim!')echo str_replace(array(’m’,’i’),’n’,'my name is jim!');$vowels = array('a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U');$onlyconsonants = str_replace($vowels, '','Hello World of PHP');echo $onlyconsonants;

知識(shí)點(diǎn)擴(kuò)展：

PHP利用str_replace防注入的方法

<?php /** * 安全過(guò)濾函數(shù) * * @param $string * @return string */ function safe_replace($string) { $string = str_replace(’%20’,’’,$string); $string = str_replace(’%27’,’’,$string); $string = str_replace(’%2527’,’’,$string); $string = str_replace(’*’,’’,$string); $string = str_replace(’'’,’&quot;’,$string); $string = str_replace('’',’’,$string); $string = str_replace(’'’,’’,$string); $string = str_replace(’;’,’’,$string); $string = str_replace(’<’,’&lt;’,$string); $string = str_replace(’>’,’&gt;’,$string); $string = str_replace('{',’’,$string); $string = str_replace(’}’,’’,$string); $string = str_replace(’’,’’,$string); return $string; } ?> <?php /** * 返回經(jīng)addslashes處理過(guò)的字符串或數(shù)組 * @param $string 需要處理的字符串或數(shù)組 * @return mixed */ function new_addslashes($string) { if(!is_array($string)) return addslashes($string); foreach($string as $key => $val) $string[$key] = new_addslashes($val); return $string; } ?> <?php //對(duì)請(qǐng)求的字符串進(jìn)行安全處理 /* $safestep 0 為不處理， 1 為禁止不安全HTML內(nèi)容(javascript等)， 2 完全禁止HTML內(nèi)容，并替換部份不安全字符串（如：eval(、union、CONCAT(、--、等） */ function StringSafe($str, $safestep=-1){ $safestep = ($safestep > -1) ? $safestep : 1; if($safestep == 1){ $str = preg_replace('#script:#i', 'ｓｃｒｉｐｔ：', $str); $str = preg_replace('#<[/]{0,1}(link|meta|ifr|fra|scr)[^>]*>#isU', ’’, $str); $str = preg_replace('#[ ]{1,}#', ’ ’, $str); return $str; }else if($safestep == 2){ $str = addslashes(htmlspecialchars(stripslashes($str))); $str = preg_replace('#eval#i', ’ｅｖａｌ’, $str); $str = preg_replace('#union#i', ’ｕｎｉｏｎ’, $str); $str = preg_replace('#concat#i', ’ｃｏｎｃａｔ’, $str); $str = preg_replace('#--#', ’－－’, $str); $str = preg_replace('#[ ]{1,}#', ’ ’, $str); return $str; }else{ return $str; } } ?> <?php /**+----------------------------------------------------------* 輸出安全的html，用于過(guò)濾危險(xiǎn)代碼+----------------------------------------------------------* @access public+----------------------------------------------------------* @param string $text 要處理的字符串* @param mixed $tags 允許的標(biāo)簽列表，如 table|td|th|td+----------------------------------------------------------* @return string+----------------------------------------------------------*/ static public function safeHtml($text, $tags = null) { $text = trim($text); //完全過(guò)濾注釋 $text = preg_replace(’/<!--?.*-->/’,’’,$text); //完全過(guò)濾動(dòng)態(tài)代碼 $text = preg_replace(’/<?|?’.’>/’,’’,$text); //完全過(guò)濾js $text = preg_replace(’/<script?.*/script>/’,’’,$text); $text = str_replace(’[’,’&#091;’,$text); $text = str_replace(’]’,’&#093;’,$text); $text = str_replace(’|’,’&#124;’,$text); //過(guò)濾換行符 $text = preg_replace(’/ ? /’,’’,$text); //br $text = preg_replace(’/<br(s/)?’.’>/i’,’[br]’,$text); $text = preg_replace(’/([br]s*){10,}/i’,’[br]’,$text); //過(guò)濾危險(xiǎn)的屬性，如：過(guò)濾on事件lang js while(preg_match(’/(<[^><]+)(lang|on|action|background|codebase|dynsrc|lowsrc)[^><]+/i’,$text,$mat)){ $text=str_replace($mat[0],$mat[1],$text); } while(preg_match(’/(<[^><]+)(window.|javascript:|js:|about:|file:|document.|vbs:|cookie)([^><]*)/i’,$text,$mat)){ $text=str_replace($mat[0],$mat[1].$mat[3],$text); } if( empty($allowTags) ) { $allowTags = self::$htmlTags[’allow’]; } //允許的HTML標(biāo)簽 $text = preg_replace(’/<(’.$allowTags.’)( [^><[]]*)>/i’,’[12]’,$text); //過(guò)濾多余html if ( empty($banTag) ) { $banTag = self::$htmlTags[’ban’]; } $text = preg_replace(’/</?(’.$banTag.’)[^><]*>/i’,’’,$text); //過(guò)濾合法的html標(biāo)簽 while(preg_match(’/<([a-z]+)[^><[]]*>[^><]*</1>/i’,$text,$mat)){ $text=str_replace($mat[0],str_replace(’>’,’]’,str_replace(’<’,’[’,$mat[0])),$text); } //轉(zhuǎn)換引號(hào) while(preg_match(’/([[^[]]*=s*)('|’)([^2=[]]+)2([^[]]*])/i’,$text,$mat)){ $text=str_replace($mat[0],$mat[1].’|’.$mat[3].’|’.$mat[4],$text); } //空屬性轉(zhuǎn)換 $text = str_replace(’’’’,’||’,$text); $text = str_replace(’''’,’||’,$text); //過(guò)濾錯(cuò)誤的單個(gè)引號(hào) while(preg_match(’/[[^[]]*('|’)[^[]]*]/i’,$text,$mat)){ $text=str_replace($mat[0],str_replace($mat[1],’’,$mat[0]),$text); } //轉(zhuǎn)換其它所有不合法的 < > $text = str_replace(’<’,’&lt;’,$text); $text = str_replace(’>’,’&gt;’,$text); $text = str_replace(’'’,’&quot;’,$text); //反轉(zhuǎn)換 $text = str_replace(’[’,’<’,$text); $text = str_replace(’]’,’>’,$text); $text = str_replace(’|’,’'’,$text); //過(guò)濾多余空格 $text = str_replace(’ ’,’ ’,$text); return $text; } ?> <?php function RemoveXSS($val) {// remove all non-printable characters. CR(0a) and LF(0b) and TAB(9) are allowed// this prevents some character re-spacing such as <javascript>// note that you have to handle splits with , , and later since they *are* allowed in some // inputs$val = preg_replace(’/([x00-x08,x0b-x0c,x0e-x19])/’, ’’, $val);// straight replacements, the user should never need these since they’re normal characters// this prevents like <IMG SRC=@avascript:alert(’XSS’)>$search = ’abcdefghijklmnopqrstuvwxyz’;$search .= ’ABCDEFGHIJKLMNOPQRSTUVWXYZ’;$search .= ’1234567890!@#$%^&*()’;$search .= ’~`';:?+/={}[]-_|’’;for ($i = 0; $i < strlen($search); $i++) { // ;? matches the ;, which is optional // 0{0,7} matches any padded zeros, which are optional and go up to 8 chars // @ @ search for the hex values $val = preg_replace(’/(&#[xX]0{0,8}’.dechex(ord($search[$i])).’;?)/i’, $search[$i], $val);//with a ; // @ @ 0{0,7} matches ’0’ zero to seven times $val = preg_replace(’/(&#0{0,8}’.ord($search[$i]).’;?)/’, $search[$i], $val); // with a ;}// now the only remaining whitespace attacks are , , and $ra1 = Array(’javascript’, ’vbscript’, ’expression’, ’applet’, ’meta’, ’xml’, ’blink’, ’link’, ’style’, ’script’, ’embed’, ’object’, ’iframe’, ’frame’, ’frameset’, ’ilayer’, ’layer’, ’bgsound’, ’title’, ’base’);$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 somethingwhile ($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{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, $val); // filter out the hex tagsif ($val_before == $val) { // no replacements were made, so exit the loop $found = false;} }}return $val; } ?>

到此這篇關(guān)于php中str_replace替換實(shí)例講解的文章就介紹到這了,更多相關(guān)php中str_replace如何替換內(nèi)容請(qǐng)搜索好吧啦網(wǎng)以前的文章或繼續(xù)瀏覽下面的相關(guān)文章希望大家以后多多支持好吧啦網(wǎng)！