## 1 截取文章里的链接
```php
$pattern = '~[a-z]+://\S+~';
preg_match_all($pattern, $link, $out)
if (empty($out[0])) exit('请输入带有链接的文本');
$link = $out[0][0];
```
## 2 curl模拟浏览器请求的方法
> 最好使用 GuzzleHttp 插件
```php
composer require guzzlehttp/guzzle
```
```php
$headers = [
'cookie' => '',
'user-agent' => 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.198 Safari/537.36',
];
$client = new Client([
'verify' => false,
'allow_redirects' => [
'max' => 0,
],
]);
$response = $client->get($link,['headers' => $headers]);
$data = $response->getBody()->getContents();
```
> curl 方式
```php
$cookie = "";
$request_link='';//请求链接
$post_data = '';//请求数据
$referer='';//刷新链接
$agent='';//代理
$header=[];//头部信息
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,$request_link);
curl_setopt($ch,CURLOPT_HTTPHEADER,$header);
curl_setopt($ch, CURLOPT_COOKIE, $cookie);
curl_setopt($ch, CURLOPT_REFERER,$referer);
curl_setopt($ch,CURLOPT_USERAGENT,$agent);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_ENCODING, 'gzip,deflate');
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
curl_setopt($ch, CURLOPT_TIMEOUT, 5);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);
$output = curl_exec($ch);
curl_close($ch);
return $output;
```
## 3 通过域名获取IP的方法
```php
gethostbyname($host)
```
## 4 随机生成字符
```php
$chars = [
1 => '0123456789abcdefghigklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ',
2 => '123456789',
3 => 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!@#$%^&*()-_ []{}<>~`+=,.;:/?|',
4 => 'abcdefghigklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
];
$str = '';
for ($i = 0; $i < $length; $i++) {
$str .= $chars[$type][mt_rand(0, strlen($chars[$type]) - 1)];
}
return $str;
```
## 5 随机生成订单号
```php
$y = date('y');
$m=date('m');
$d=date('d');
$h=date('h');
$i=date('i');
$s=date('s');
$date=ceil($y+$m+$d).ceil($h+$i+$s);
$digits = intval($digits);
if ($digits < 14) return '随机单号大于14字符';
$digits = $digits - strlen($date) - strlen($prefix);
if ($digits < 0) return '随机单号生成失败';
$rand = '';
$num = floor($digits / 10);
for ($i = 0; $i < $num; $i++) {
$rand .= str_pad(mt_rand(1, (int)9999999999), 10, '0', STR_PAD_LEFT);
}
if ($digits % 10 != 0) {
$rand .= str_pad(mt_rand(1, (int)substr(9999999999, 0, $digits - ($num * 10))), $digits - ($num * 10), '0', STR_PAD_LEFT);
}
$order_number = $prefix . $date . $rand;
return $order_number;
```
## 6 截取字符串，两个字符中间的内容
```php
$string = ' ' . $string;
$ini = strpos($string, $start);
if ($ini == 0) return '';
$ini += strlen($start);
$len = is_null($end)?strlen($string)-$ini:strpos($string, $end, $ini) - $ini;
return substr($string, $ini, $len);
```
