PHP Chinese website shows you how to operate php files

* Basic process of file operation

* 1. Open the file

* 2. Operate the file: read, write, append, etc.

* 3. Close the file

//1. Create or open a local file

//Open the file in r (read-only) mode, no new file will be created, similar to: r (read-write), the pointer is at the beginning

// $fh = fopen('file1.txt', 'r') or die("Cannot open file1.txt file");

//Open in w (write-only) mode File, if the file does not exist, create it, similar to: w (read and write), the pointer is at the beginning

$fh = fopen('file2.txt', 'w') or die("不能打开file2.txt文件");

//Open the file in a (append write only) mode, if the file does not exist, create it, similar to: a (Append read and write), the pointer is at the end

$fh = fopen('file3.txt', 'a') or die("不能打开file3.txt文件");

//Note: It is recommended to add b to the read and write mode symbols on Windows machines to enhance compatibility with binary files, such as rb, wb...

//2.Open a remote file

$fh = fopen('http://www.php.cn/course/801.html', 'r');

//3.Read the file to the browser

//Read a line from the file pointer and automatically move it down

// while ($s = fgets($fh)) {

// print $s;

// }

//fgetss( ) can filter out all html tags

// while ($s = fgetss($fh)) {

// print $s;

// }

//4. Read the file into a string:

//file_get_contens($filename) returns a string

// $content = file_get_contents('file.txt' );

//Read the entire page into a string, which is very useful when crawling content from other websites, in conjunction with filtering rules

// $content = file_get_contents('http: //www.php.cn');

// echo 'File size: '.strlen($content).' bytes', '
';

/ / if (strlen($content) > 0) {

// echo $content;

// }

//5. Read the entire file into In the array, use newline characters to split

$arr ​​= file('maxim.txt');

// foreach ($arr as $key => $value) {

// echo 'motto'.($key 1).': '.$value.'

---

';

// }

// shuffle($arr), randomly shuffle an array, return true/false

// if (shuffle($arr)) {

// echo current($arr); //Display a random motto

// echo $arr[0]; //Display a random motto

// }

echo '

---

';

//array_rand($arr,$length=1): Randomly remove one or more elements from the array

/ /Take out one and return only the key name, if multiple, return an array of random key names

// echo $arr[array_rand($arr)];

print_r(array_rand($arr,3));//返回三个随机的键名
echo &#39;<hr>&#39;;

// Traverse this key name array, Query the corresponding array element value

$kes = array_rand($arr,3);
foreach ($kes as $value) { //键名无意义,我们只关心值,即键名
print $arr[$value].&#39;<hr>&#39;;
}

//After the file reading and writing is completed, it should be closed in time

fclose($fh);

//After closing the script, the file will also be automatically closed, but manual display is still highly recommended This is a good habit