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1. File upload 1. Client settings: (1) Indicate the corresponding values of the enctype and method attributes in the tag. &nb […]
1. File upload
1. Client settings:
(1), in
2. File download
To download a simple file, you only need to use the HTML link tag and specify the URL value of the href attribute to the downloaded file. This method can only handle some MIME type files that the browser cannot recognize.
In order to improve security, if you do not want to give a file link in the a tag, you must send the necessary header information to the browser. We can use the following code.
3. File function library
touch
Set file access and modification time
bool touch(string $filename[, int $time[, int $time]])
copy
Copy file
bool copy(string $source, string $dest)
Note: Please use the rename function to move files
file_put_contents
Write a string to a file
int file_put_contents(string $filename, string $data[, int $flag[, resource $content]])
file_get_contents
Read the entire file into a string
string file_get_contents(string $filename[, bool user_include_path [, resource $content[, int $offset[, int $maxlen]]]])
4. Serialization and Deserialization
serialize
Serialization
string serialize(mixed $value)
Note: serialize() can handle any type except resouce. You can even serialize() arrays that contain references to themselves.
unserialize
Deserialization
mixed unserialize(string $str)
● date
Format a local time/date
string date(string format[, int timestamp]);
● getdate
Get date/time information
array getdate([int timestamp]);
● microtime
Returns the current Unix timestamp and microseconds
mixed microtime([bool get_as_float]);
● date_default_timezone_set
Set default time zone
bool date_default_timezone_set(string timezone_identifier);
● date_default_timezone_get
Get default time zone
string date_default_timezone_get(void);
3. Character function library
strlen
Get the string length
int strlen(string $str);
strtolower
Convert string to lower case
string strtolower(string $str);
strtoupper
Convert string to uppercase
string strtoupper(string $str);
ucfirst
Capitalize the first letter
string ucfirst(string $str);
ucwords
Convert the first letter of each word to uppercase
string ucwords(string $str);
ltrim
Remove spaces or other characters from the beginning of the string
string ltrim(string $str [, string $charlist]);
rtrim
Remove spaces or other characters from the end of the string
string rtrim(string $str[, string $chirlist]);
trim
Remove spaces or other characters from the beginning and end of the string
str_replace
Character replacement
mixed str_ireplace(mixed $search, mixed $replace, mixed $subject, [int $count]);
str_ireplace
Character replacement
mixed str_ireplace(mixed $search, mixed $replace, mixed $subject, [int $count]);
md5
Calculate MD5 hash of string
string md5(string $str[, bool $raw_output=false]);
strpos
Returns the position of the first occurrence of one character in another character
int strpos(string haystack, mixed needle[, int offset]);