<?php //没有参数的自定义函数 function sum(){ for ($i = 0 ; $i <= 100; $i++){ $sum += $i; } echo $sum; } sum(); echo ‘中国‘; sum();
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<?php //封装自定义函数,可以计算任意数字到另一个数字之间的和 function sum ($start, $end) { for ($i = $strart; $i <= $end ; $i++){ $sum += $i; } echo $sum; } $strart = 1; $end = 100; sum($strart,$end); sum(1,10);
//////////////////////////////////////////////// <?php //自定义函数,获取文件的扩展名 function getExtension($filename) { $extension = strtolower (substr($filename,strrpos($filename, ‘.‘) + 1)); echo $extension; } getExtension (‘a.gif.jpg.png‘);
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<?php //将任意的关联数组的键名和键值连接成如下结构 //$arr = [‘username‘ => ‘tom‘ , ‘password‘ => ‘123‘ , ‘age‘ => 22] //连接的结果是: //INSET INTO ?(username, password, age) VALUES(‘Tom‘, ‘123‘, ‘22‘) //该自定义函数的名称为 insert function insert($array) { $fields = implode(‘,‘, array_keys($array)); $values = “‘” . implode(“‘,‘”, $array) . “‘”; $sql = “INSERT INTO ?({$fields}) VALUES ({$values})”; echo $aql; } $array = [‘username‘ => ‘tom‘, ‘password‘ => ‘123‘, ‘age‘ => 22]; insert($array);
//将任意的关联数组的键名和键值连接成如下结构 //$arr = [‘username‘ => ‘tom‘ , ‘password‘ => ‘123‘ , ‘age‘ => 22] //连接的结果是: //UPDATE? SET username=‘‘Tom‘, password=‘123‘, age=‘22‘ //该自定义函数的名称为 update function update($array) { foreach($array as $fields => $value){ $sql .= $fields . ‘=\‘‘ . $value . ‘\‘,‘; } $sql = substr($sql, 0, -1); $sql = “UPDATE ? SET ” .$sql; echo $sql; } $arr = [‘username‘ => ‘tom‘, ‘password‘ => ‘123‘, ‘age‘ => 22]; update($arr);
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<?php //产生随机字符的函数,长度默认为4位 function random($type, $length = 4) { //数字型 if($type == 1){ $chars = ‘0123456789‘; }else if($type == 2){ //字母型 $chars = ‘ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz‘; }else { //混合型 $chars = ‘23456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghjklmnpqrstuvwxyz‘; } $chars = substr(str_shuffle($chars), 0, $length); echo $chars; } random(1); random(1,6); random(2);
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<?php //可以计算至少两个数字以上的数字的平均值 //PHP5.6之后的版本 function avg(…$avg) { $sum = array_sum($arg); $number = count($arg); echo round($sum / $number,2); } avg(1,3); avg(1,2,7); avg(1,,2,3,4);
//PHP5.6之前的版本 function average() { print_r(func_get_args()); } average(1,3); average(1,3,5); average(1,3,5,8);
//// function average() { echo ‘索引位置为1的参数值是:‘ , func_get_arg(1); } average(1,3); average(1,3,5); average(1,3,5,8);
////////// function average() { echo ‘共有‘ , func_num_args(), ‘个参数‘; } average(1,2); average(1,4,5); average(1,9,5,8);
///////////php5.6之前的版本 function average() { $args = func_get_args(); $sum = array_sum($args); $number = func_num_args(); echo $sum / $number; } average(1,2); average(1,4,5); average(1,,9,5,8);