2013-10-08 code小结

<?php
header('Content-Type:text/html;charset=utf-8');
//预先定义字串并格式化输出-------------------------------------------------------

$name='mark';
$sex='femel';
$age='20';
$hobby='swimming';
printf('名字是%s年龄是%d性别是%s爱好是%s',$name,$age,$sex,$hobby);
//预先定义字串-------------------------------------------------------------------------
echo "<hr/>";
$new=sprintf('名字是%s年龄是%d性别是%s爱好是%s',$name,$age,$sex,$hobby);
echo $new;

//去除两边空格-------------------------------------------------------------------------
echo "<hr/>";
$str=' hello ';
echo strlen($str);
echo "<br/>";
echo strlen(trim($str));

//去左边空格/去除右边空格------------------------------------------------------------
echo "<hr/>";
$str1=' world';
echo strlen($str1);
echo "<br/>";
echo strlen(ltrim($str1));
echo "<br/>";
echo strlen(rtrim($str1));

//去掉字符串两边的多余的数字和符号----------------------------------------------
echo "<hr/>";
$str2='1234work++*';
$new1=trim($str2,'0..4 + *');//一参指定字符串//二参指定去除的字符的范围或本体
echo $new1;
//字符串的填充----------------------------------------------
echo "<hr/>";
$str3='hello';
echo str_pad($str,'11','*',STR_PAD_BOTH).'||';
//一参指定字符串，二参指定长度，三参指定填充符号，四参添加位置
echo str_pad($str,'11','*',STR_PAD_RIGHT).'||';
echo str_pad($str,'11','*',STR_PAD_LEFT);

//测量字符串长度---------------------------------------------------
echo "<hr/>";
$str4=' hello ';//普字符占一位  汉字符占三位
$count=strlen($str4);
echo $count;
//全部大写、全部小写、语句首字大写、单词首字大写----------------------
echo "<hr/>";
$str5='lamp is from to linux apche mysql php.';
echo strtoupper($str5).'<br/>';//全部大写
echo strtolower($str5).'<br/>';//全部小写
echo ucfirst($str5).'<br/>';//语句首字大写
echo ucwords($str5).'<br/>';//单词首字大写
//strip_tags — 从字符串中去除 HTML 和 PHP 标记(表单安全过滤)---------------
echo "<hr/>";
$str6='<font color=red>我是红色！</font>';
$result=strip_tags($str6);
echo $result.$str6;
//stripslashes返回反转义后的字符串-----(表单安全过滤)------------------------
echo "<hr/>";
$str7='我是'.'<font color=green>反转义的</font>'.'字符串';
$new_str=stripslashes($str7);
echo $new_str.$str7;
//htmlspecialchars-将表单内容实体输出-------------------
//nl2br — 在字符串所有新行之前插入 HTML 换行标记---------------

//千分制进位（货币）---------------------------------------------------------------------
echo "<hr/>";
$price=500066.59;
echo number_format($price,2);	//第二个参数限制小数点保留位数
//字符串翻转的函数----------------------------------------------------------------
echo "<hr/>";
$str = "admin";
echo strrev($str).'<br/>'; 
//加密函数,通常用来对密码加密----------------------------------------------------
echo "<hr/>";
$pass = 'admin123';
echo md5($pass);
//比较字符串大小--------------------------------------------------------
echo "<hr/>";
$str = "Admin";
$new_str = 'admin';
echo strcmp($str,$new_str);    //如果第一个参数的字节数大于第二个参数，返回1，如果小于返回-1；如果相等返回0
strcasecmp($str,$new_str);	//case代表忽略大小写之后再做比较
//strcmp按照元素的字节数排序----------------------------------------------
//strnatcmp	按照自然数排序--------------------------------------------------
//字符串分割、粘贴----------------------------------------------
echo "<hr/>";
$str = "10/08/2013";
$arr = explode('/',$str);		//爆炸 ,参数1，分隔符，参数2，待分割的字符串
nl2br(print_r($arr));
echo "今天是{$arr[1]}号";
echo "<br/>";
//将数组元素拼接成一个字符串
$new_arr = array('男人','女人','人妖');
$new_str = implode('==>',$new_arr);		//参数1，分隔符(用什么符号链接)  参数2，数组
echo $new_str;