PHP concise function (PHP simple and clear function syntax)_PHP tutorial

1. Related to mysql

mysql_connect
Establish a connection with the MySQL server
Syntax


resource mysql_connect(string server[,string usingname[,string password[, bool new_link[,int client_flags]]]])
eg:

Copy code The code is as follows:

$DB_HOST ="localhost";
$DB_LOGIN ="root";
$DB_PASSWORD =" 123456";
$conn=mysql_connect($DB_HOST,$DB_LOGIN,$DB_PASSWORD);

mysql_data_seek
Move the internal query pointer to the query row
Syntax

bool mysql_data_seek(resource result_indetifier,int row_number)
eg:

Copy code The code is as follows:

$DB_HOST ="localhost";
$DB_LOGIN ="root";
$DB_PASSWORD = "123456";
$DB_NAME ="flag";
$conn=mysql_connect($DB_HOST,$DB_LOGIN,$DB_PASSWORD);
mysql_select_db($DB_NAME);
$res=mysql_query(" SELECT * FROM PRODUCT");
$row=mysql_fetch_array($res);
for($i=0;$i<$num;$i++)
$row=mysql_fetch_array($res);
mysql_data_seek($res,0);//Move the pointer back to the first row of the query result

mysql_fetch_array
Save the query result In the array (each array element stores a record)
Syntax

array mysql_fetch_array(resource result[,int result_type])
eg

Copy code The code is as follows:

$DB_HOST ="localhost";
$DB_LOGIN ="root";
$DB_PASSWORD ="123456";
$DB_NAME ="flag";
$conn=mysql_connect($DB_HOST,$DB_LOGIN,$DB_PASSWORD);
mysql_select_db($DB_NAME);
$res=mysql_query("SELECT * FROM PRODUCT");
$row=mysql_fetch_array($res);

mysql_fetch_object
Get a row of query results and store it as an object type, which is exactly the same as MySQL_fetch_array(). The difference is that mysql_fetch_object() can only obtain query results through field names
echo $row->fieldname; //Correct usage
echo $row->0; //Incorrect usage
Syntax

object mysql_fetch_object(resource result)
eg

Copy code The code is as follows:

$DB_HOST = "localhost";
$DB_LOGIN ="root";
$DB_PASSWORD ="123456";
$DB_NAME ="flag";
$conn=mysql_connect($DB_HOST,$DB_LOGIN,$DB_PASSWORD );
mysql_select_db($DB_NAME);
$res=mysql_query("SELECT * FROM PRODUCT");
$row=$mysql_fetch_object($res);
while($row)
{
echo $rowàp_id;
echo $rowàp_name;
}

mysql_insert_id
After using the INSERT command to add a piece of information, you can Use this function to obtain the unique id of the record just added
Syntax

int mysql_insert_id([esource link_identifier])
eg

Copy code The code is as follows:

$DB_HOST ="localhost";
$DB_LOGIN ="root";
$DB_PASSWORD ="123456";
$DB_NAME ="flag" ;
$conn=mysql_connect($DB_HOST,$DB_LOGIN,$DB_PASSWORD);
mysql_select_db($DB_NAME);
$SQLStr"INSERT INTO produce (p_id,p_name)VALUES('','PHP book ')";
$res=mysql_query($res);
$p_id=mysql_insert_id();

mysql_num_rows
Get the number of rows in the query result
Syntax

int mysql_num_rows(resource result)
eg

Copy code The code is as follows:

$DB_HOST ="localhost";
$DB_LOGIN ="root";
$DB_PASSWORD ="123456";
$DB_NAME ="flag";
$conn=mysql_connect($DB_HOST,$ DB_LOGIN,$DB_PASSWORD);
mysql_select_db($DB_NAME);
$res=mysql_query("SELECT * FROM PRODUCT");
$num=mysql_num_rows($res);

mysql_query
Send a SQL syntax query statement
Syntax

resource mysql_query(string query[,resource link_identifier])
eg

Copy code The code is as follows:

$DB_HOST ="localhost";
$DB_LOGIN ="root";
$DB_PASSWORD="123456";
$DB_NAME ="flag";
$conn=mysql_connect($DB_HOST,$DB_LOGIN,$DB_PASSWORD);
mysql_select_db($DB_NAME);
$res=mysql_query("SELECT * FROM PRODUCT ");

mysql_select_db
Select the name of the database to be accessed
Syntax

bool mysql_select_db(string database_name[,resource link_identifier])
eg

Copy code The code is as follows:

$DB_HOST ="localhost";
$DB_LOGIN ="root";
$DB_PASSWORD ="123456";
$DB_NAME ="flag";
$conn=mysql_connect ($DB_HOST,$DB_LOGIN,$DB_PASSWORD);
mysql_select_db($DB_NAME);

2. File system function
copy
Copy text
Syntax
bool copy(string source,string dest)
eg

Copy code The code is as follows:

copy("abc. txt","/tmp/newabc.txt");

fclose
Close an open file pointer
Syntax
bool fclose(resource handle)
eg

Copy code The code is as follows:

$fp=fopen("abc.txt","w");
fclose($fp);

fgets
Get the contents of the column from the position pointed to by the file pointer
Syntax
string fgets(resource handle[,int length])
eg

Copy code The code is as follows:

$fp=fopen("abc.txt","w");
$txtdata= fgets($fp,4096);

file
Read the entire file content into an array
Syntax
array file(string filename[,int use_include_path [,resource context]])
eg

Copy code The code is as follows:

$content=file("abc .txt");

file_exists
Check if the file exists
Syntax

bool file_exists(string filename)
eg

Copy code The code is as follows:

if (file_exists("abc.txt"))
echo "This file exists";
else
echo "This file does not exist";

filesize
Get file size
Syntax
int filesize(string filename)
eg

Copy code The code is as follows:

$size=filesize("abc.txt");

fopen
Open a file or url
Syntax
resource fopen (string filename,string mode[,bool use-include_path[,resource zcontext]])
eg

Copy code The code is as follows:

$fp=fopen("abc.txt");
$fp=fopen("http://www.jb51 .net/bacteroid/","r");

fputs
Write data to the file
Syntax
int fputs(resource handle,string string[ ,int length])
eg

Copy code The code is as follows:

$fp=fopen("abc.txt ");
fputs($fp,"helloworld!");

fseek
Set the position pointed by the file pointer
Syntax
int fseek( resource handle,int offset[,int whence])
eg

Copy code The code is as follows:

$fp= fopen("abc.txt","w");
$txtdata=fgets($fp,4096);
fseek($fp,0);//Point the pointer back to the beginning

mkdir
Create a directory
Syntax
bool mkdir(string pathname[,int mode[,bool recursive[,resource context]]])
eg

Copy code The code is as follows:

mkdir("ljt/newfolder");

unlink
Delete file
Syntax
int unlink(string filename);
eg

Copy code The code is as follows:

unlink("abc.txt");

3. Date and time functions
data
Return the local time/date in the specified format
Syntax
string date(string format[,int timestamp])
eg

Copy code The code is as follows:

$time =date("Y-m-d g:i:s");

getdate
Get date and time information
Syntax
array getdata([int timestamp ])
eg

Copy code The code is as follows:

$now=getdate();
$year =$now["year"];
$month=$now["month"];

gettimeofday
Get the current time (including GMT)
Syntax
array gettimeofday(void)
eg

Copy code The code is as follows:

$time=gettimeofday();

4. String processing function
explode
according to the specified separation Split the string into an array
Syntax
array explode(string separator,string string[,int limit])
eg

Copy code The code is as follows:

$str="a,b,c";
$res=explode(",",$str);//$res[0] =a

implode
Concatenate the array contents into a string
Syntax
string implode(string glue,array pieces)
eg

Copy code The code is as follows:

$newarray=array('a','b','c');
$ res=implode(",",$newarray);//$res=a,b,c

strlen
Get the length of the string
Syntax
int strlen( string string)
eg

Copy code The code is as follows:

strlen("www.jb51.net"); //Return 15
[c/ode]
substr
Get a certain part of the characters (substring) specified by the string
Syntax
string substr("www.gxnu.edu. cn",1,7); //Return "ww.gxnu"
5. Mathematical function library
Unconditionally carry the decimal part of the floating point number
Syntax
float ceil(float value)
eg
[code]
echo ceil(9.99);//Return 10
echo ceil(9.12);//Return 10

cos
Get floating point number Cosine of value
Syntax
float cos(float arg)
eg

Copy code The code is as follows:

$numcos=cos(0.5);

floor
Unconditionally remove the decimal part of the floating point number
Syntax
float floor(floor value)
eg

Copy code The code is as follows:

echo floor(9.12);//Return 9
echo floor(9.99); // Return 9

rand
Generate a range of random values ​​
Syntax
i
nt rand([int min,in max])
eg

Copy code The code is as follows:

$num=rand(0,100);//Generate a number between 1 and 100 Random value

round
Round the decimal part of the floating point number
Syntax
float round(float value)
eg

Copy code The code is as follows:

float round(9.99)//returns 10
float round(9.12)//returns 9

sin
Get the sine value of a floating point value
Syntax
float sin(float arg)
eg

Copy code The code is as follows:

$numsin=sin(0.5);

6. Session function
session_register
Describes one or more Sessions The variable
syntax
bool session_register(mixed name[,mixed...])
eg

Copy code The code is as follows:

$name="flag";
session_register("name");

session_start
Initialize Session information
Syntax
bool session(void)
eg

Copy code The code is as follows:

session_start();

7. Array function
count
Calculate how many array functions there are in the array
Syntax
int count(mixed var[,int mode])
eg

Copy code The code is as follows:

count($array);

list
Assign the element value in the array to the variable
Syntax
void list(mixed varname,mixed...)
eg

Copy code The code is as follows:

$array=array(a,b,c);
list($str1,$str2,$str3)=$array;//$str1=a

range
Create an array within the specified range
Syntax
array range(int low,int high[,int step])
eg

Copy code The code is as follows:

$array=array(0,9);

shuffle
shuffle the array The elements in are randomly reordered
Syntax
bool shuffle(array array)
eg

Copy code The code is as follows:

shuffle($array);

Author: Bacteroides

http://www.bkjia.com/PHPjc/325584.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/325584.htmlTechArticle1. Mysql-related mysql_connect establishes a connection with the MySQL server syntax resource mysql_connect(string server[,string usingname[ ,string password[, bool new_link[,int client_f...