/*常用的字符串輸出函數(shù)
*
* echo() 輸出字符串
* print() 輸出一個(gè)或多個(gè)字符串
* die() 輸出一條信息，并退出當(dāng)前腳本
* printf() 輸出格式化字符串
* sprintf() 把格式化的字符串寫入到一個(gè)變量中
*
*/
//ucfirst 
//將字符串中的首字母轉(zhuǎn)換為大寫
$str="string";
echo ucfirst($str);
echo "<hr><br/>";
//ucwords()
//將字符串中的每個(gè)單詞的首字母大寫
$ucword="hello everyone!";
echo ucwords($ucword);
echo "<hr><br/>";
//ltrim() rtrim() trim()
//去除空格
$str="123 This is a test.....";
echo ltrim($str,"0..9")."<br/>"; //去除左側(cè)的數(shù)字 
echo rtrim($str,".")."<br/>";
echo trim($str,"0..9A..Z.")."<br/>"; //去除字符串兩端的大寫字母，數(shù)字還有.
//HTML相關(guān)的字符串格式化函數(shù)
//nl2br()
//將字符串中的\n轉(zhuǎn)換為"<br/>"
$str="this is \n hello world";
echo nl2br($str).'<br/>';
//htmlspecialchars()
//將html標(biāo)記以字符的形式顯示，不進(jìn)行解釋
$str="<b>hello world</b>";
echo $str."<br/>";
echo htmlspecialchars($str);
echo "<hr><br/>";
//addcslashes
//添加反斜線
$str=addcslashes("foo[]","A..z");
echo $str."<br/>";
echo addcslashes("zoo['.']",'A..z')."<br/>";
//convert_uuencode()
//利用uudecode的方法對(duì)字符串進(jìn)行編碼
$string="hello world";
$str= convert_uuencode($string);
echo $str."<br/>";
echo convert_uudecode($str)."<br/>";
//html_entity_decode ( string $string [, int $flags = ENT_COMPAT | ENT_HTML401 [, string $encoding = 'UTF-8' ]] )
//與htmlentities方法相反，將進(jìn)行編碼后的html字符轉(zhuǎn)換為瀏覽器能夠編譯的形式
$a="I want a bright <b>future</b>";
$b= htmlentities($a)."<br/>";
echo $b;
echo html_entity_decode($b);
echo "<hr><br/>";
//htmlspecialchars_decode ( string $string [, int $flags = ENT_COMPAT | ENT_HTML401 ] )
//與htmlspecialchars函數(shù)相反，將HTML實(shí)體轉(zhuǎn)換為字符
$c=htmlspecialchars($a);
echo $c."<br/>";
echo htmlspecialchars_decode($c)."<br/>";
echo "<hr><br/>";
//lcfirst ( string $str )
//將字符串的首字符小寫
$str="Hello World";
// echo lcfirst($str)."<br/>";
//md5_file ( string $filename [, bool $raw_output = false ] )
//對(duì)文件進(jìn)行md5加密
//
$string="password";
$str=md5($string);
if($str=="5f4dcc3b5aa765d61d8327deb882cf99"){
 echo "The password is right <br/>";
}
//parse_str ( string $str [, array &$arr ] )
//將一個(gè)字符串進(jìn)行解析，解析成變量和數(shù)組的形式
$str = "first=value&arr[]=foo+bar&arr[]=baz";
parse_str($str,$input);
print_r($input);
echo "<hr><br/>";
//string sha1_file ( string $filename [, bool $raw_output = false ] )
//計(jì)算文件的散列值
foreach(glob("C:/lamp/appache2/htdocs/*.php") as $ent){
 if(is_dir($ent)){
 continue;
 }
 echo $ent."(SHA1:".sha1_file($ent).")<br/>";
}
echo "<hr><br/>";
//int similar_text ( string $first , string $second [, float &$percent ] )
//計(jì)算兩個(gè)字符串的相似度,通過(guò)引用方式傳遞第三個(gè)參數(shù)，similar_text() 將
//計(jì)算相似程度百分?jǐn)?shù)。
$string1="rogerzhalili";
$string2="zhangjieroger";
if(similar_text($string1,$string2,$percent)){
 echo $string1." and ".$string2." has the similarity of:".$percent."<br/>";
}
echo "<hr><br/>";
//string str_shuffle ( string $str )
//打亂一個(gè)字符串
$string="I want you to solve this problem";
echo str_shuffle($string)."<br/>";
//array str_split ( string $string [, int $split_length = 1 ] )
//按照指定的長(zhǎng)度對(duì)字符串進(jìn)行分割
$arr=str_split($string,3);
//str_word_count ( string $string [, int $format = 0 [, string $charlist ]] )
//統(tǒng)計(jì)字符串中單詞的數(shù)量
echo "<hr><br/>";
//int strripos ( string $haystack , string $needle [, int $offset = 0 ] )
//以不區(qū)分大小寫的方式查找指定字符串在目標(biāo)字符串中最后一次出現(xiàn)的位
//置。與 strrpos() 不同，strripos() 不區(qū)分大小寫。
//offset用于指定從那個(gè)位置開始查找
$haystack='ababcd';
$needle='Ab';
echo "the last".$needle."postion is:".strripos($haystack,$needle)."<br/>";
echo strrpos($haystack,'ab');
echo "<hr><br/>";
//string strstr ( string $haystack , mixed $needle [, bool $before_needle = false ] )
//返回 haystack 字符串從 needle 第一次出現(xiàn)的位置開始到 haystack 結(jié)
//尾的字符串。 該函數(shù)區(qū)分大小寫。如果想要不區(qū)分大小寫，請(qǐng)使用
//stristr()。
$a="the First test";
$needle="Fi";
echo strstr($a,$needle)."<br/>";
if($c=strstr($a,"Fio")){
 echo "find".$c."<br/>";
}
else
{
 echo "not find the string!<br/>";
}
echo "<hr><br/>";
//int substr_count ( string $haystack , string $needle [, int $offset = 0 [, int $length ]] )
//查找$needle子字符串在$haystack中出現(xiàn)的次數(shù),$needle區(qū)分大小寫
$hay="la la wa la wa wa lala";
echo substr_count($hay,"la")."<br>";
//int preg_match_all ( string $pattern , string $subject [, array &$matches [, int $flags = PREG_PATTERN_ORDER [, int $offset = 0 ]]] )
//正則匹配，將匹配后的結(jié)果存放到$matches(如果指定了$matches的話）
preg_match_all("/?(\d3)?? (?(1) [\-\s] ) \d{3}-\d{4}/x",
"Call 555-1212 or 1-800-555-1212", $phones);
echo "<pre>";
print_r($phones);
echo "</pre>";
echo "<hr><br/>";
//preg_replace ( mixed $pattern , mixed $replacement , mixed $subject [, int $limit = -1 [, int &$count ]] )
//搜索subject中匹配pattern的部分, 以replacement進(jìn)行替換.
$string = 'April 15, 2003';
$pattern = '/(\w+) (\d+), (\d+)/i';
$replacement = '${1}1,$3';
echo preg_replace($pattern,$replacement,$string);
echo "<hr><br/>";
//array preg_split ( string $pattern , string $subject [, int $limit = -1 [, int $flags = 0 ]] )
//通過(guò)一個(gè)正則表達(dá)式分隔給定字符串.
$str = 'string';
$chars = preg_split('//', $str, -1, PREG_SPLIT_NO_EMPTY);
print_r($chars);