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PHP Notes: Instructions for using PHP functions range() round() and list()_PHP Tutorial
- WBOYOriginal
- 2016-07-21 15:11:011425browse
一>>
range()函数快速创建数组的简单方法,使用low到high范围的整数值填充数组,函数将返回一个包含次范围内所有整数的数组.形式如下
array range(int low,int high[,int step])
典型用法如下
例子:建立1-6的6个数字的数组(骰子)
$die = range(0,6);
建立0-30所有双数的数组
$even = (0,20,2);//步长为2
这个函数不仅仅可以用作数字,还可以用作字母.
如
$words = range('A','Z');
将建立包含A到Z的的所有字母的数组.此处可以用于生成验证码函数.
二>>
round()函数
这个函数是怕我记混淆了.这个函数和上面的哪个range()是天壤之别.
这个函数的作用是
取浮点数的精度
float round(float var[,int preisin})
典型用法
例: $pi = 3.141592653;
round($pi,4);
echo $pi;
将输出 3.1415
三>>
list()函数
list()函数可以在一次操作中从一个数组内提取多个值.同时为变量赋值.形式如下
void list(mixed)
典型用法
<code><code>
代码如下:
$info = array('coffee', 'brown', 'caffeine');
// Listing all the variables
list($drink, $color, $power) = $info;
echo "$drink is $color and $power makes it special.n";
// Listing some of them
list($drink, , $power) = $info;
echo "$drink has $power.n";
// Or let's skip to only the third one
list( , , $power) = $info;
echo "I need $power!n";
?>
<code><span style="LINE-HEIGHT: 1.5; FONT-FAMILY: 宋体, Verdana, Arial, Helvetica, sans-serif; COLOR: #000000"><span style="FONT-FAMILY: Courier New"><span style="LINE-HEIGHT: 1.5; FONT-FAMILY: 宋体, Verdana, Arial, Helvetica, sans-serif; COLOR: #0000bb">上例摘自PHP手册</span></span></span>
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<span style="CURSOR: pointer" onclick="doCopy('code98313')"><u>复制代码</u></span> 代码如下:</div>
<div class="codebody" id="code98313">
<br><?php <br><br>$info = array('coffee', 'brown', 'caffeine'); <br><br>// Listing all the variables <BR>list($drink, $color, $power) = $info; <BR>echo "$drink is $color and $power makes it special.n"; <br><br>// Listing some of them <BR>list($drink, , $power) = $info; <BR>echo "$drink has $power.n"; <br><br>// Or let's skip to only the third one <BR>list( , , $power) = $info; <BR>echo "I need $power!n"; <br><br>?> <br>
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$info = array('coffee', 'brown', 'caffeine');
// Listing all the variables
list($drink, $color, $power) = $info;
echo "$drink is $color and $power makes it special.n";
// Listing some of them
list($drink, , $power) = $info;
echo "$drink has $power.n";
// Or let's skip to only the third one
list( , , $power) = $info;
echo "I need $power!n";
?>
<code><span style="LINE-HEIGHT: 1.5; FONT-FAMILY: 宋体, Verdana, Arial, Helvetica, sans-serif; COLOR: #000000"><span style="FONT-FAMILY: Courier New"><span style="FONT-FAMILY: 宋体; COLOR: #0000bb">可以用list()配合正则来切割字符串存入变量表</span></span></span>
<code><span style="LINE-HEIGHT: 1.5; FONT-FAMILY: 宋体, Verdana, Arial, Helvetica, sans-serif; COLOR: #000000"><span style="FONT-FAMILY: Courier New"><span style="LINE-HEIGHT: 1.5; FONT-FAMILY: 宋体, Verdana, Arial, Helvetica, sans-serif; COLOR: #0000bb">上例摘自PHP手册</span></span></span>
<code>典型用法
<code><span style="LINE-HEIGHT: 1.5; FONT-FAMILY: 宋体, Verdana, Arial, Helvetica, sans-serif; COLOR: #000000"><span style="FONT-FAMILY: Courier New"><span style="FONT-FAMILY: 宋体; COLOR: #0000bb">可以用list()配合正则来切割字符串存入变量表</span></span></span>
<code>典型用法<code>list($name,$occupation,$color) = exolode("|",$line);
TechArticle
一 range()函数快速创建数组的简单方法,使用low到high范围的整数值填充数组,函数将返回一个包含次范围内所有整数的数组.形式如下 array ra...