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PHP concise function
Theme: Bacteroides PHP concise function
Brief description: PHP simple and clear function syntax
Suitable for people: interested in the open source community, interested in php, have a little time to understand php
Remarks: I hope everyone throws bricks and eggs, haha
1. Related to mysql
mysql_connect
Establish a connection with the MySQL server
Syntax

Copy code The code is as follows:

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

Copy code The code is as follows:

 
bool mysql_data_seek(resource result_indetifier,int row_number) 
eg: 
$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 

Store the query results in the array (each array element stores a record)
Syntax

Copy code The code is as follows:

 
array mysql_fetch_array(resource result[,int result_type ]) 
eg 
$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. The usage method is exactly the same as MySQL_fetch_array(). The difference is that mysql_fetch_object() can only obtain the query results through the field name
echo $row ->fieldname; //Correct usage
echo $row->0; //Incorrect usage

Syntax

Copy codeThe code is as follows:

 
object mysql_fetch_object(resource result) 
eg 
$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

Copy code The code is as follows:

 
int mysql_insert_id([esource link_identifier]) 
eg 
$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

Copy the code The code is as follows:

 
int mysql_num_rows(resource result) 
eg 
$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

Copy codeThe code is as follows:

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

选择欲存取的数据库名称
语法

复制代码代码如下:

 
bool mysql_select_db(string database_name[,resource link_identifier]) 
eg 
$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、文件系统函数
copy
复制文本
语法
bool copy(string source,string dest)
eg
copy(“abc.txt”,”/tmp/newabc.txt”);
fclose
关闭一个打开文件的指针
语法
bool fclose(resource handle)
eg
$fp=fopen(“abc.txt”,”w”);
fclose($fp);
fgets
从文件指针所指位置取得列的内容
语法
string fgets(resource handle[,int length])
eg
$fp=fopen(“abc.txt”,”w”);
$txtdata= fgets($fp,4096);
file
将整个文件内容读到数组中
语法
array file(string filename[,int use_include_path[,resource context]])
eg
$content=file(“abc.txt”);
file_exists
检查文件是否存在
语法
bool file_exists(string filename)
eg
if (file_exists(“abc.txt”))
echo “此文件存在”;
else
echo”此文件不存在”;
filesize
取得文件大小
语法
int filesize(string filename)
eg
$size=filesize(“abc.txt”);
fopen
打开一个文件或者url
语法
resource fopen (string filename,string mode[,bool use-include_path[,resource zcontext]])
eg
$fp=fopen(“abc.txt”);
$fp=fopen(“http://www.jb51.net/bacteroid/”,”r”);
fputs
将数据写至文件中
语法
int fputs(resource handle,string string[,int length])
eg
$fp=fopen(“abc.txt”);
fputs($fp,”helloworld!”);
fseek
设置文件指针所指的位置
语法
int fseek(resource handle,int offset[,int whence])
eg
$fp=fopen(“abc.txt”,”w”);
$txtdata=fgets($fp,4096);
fseek($fp,0);//将指针指回起始处
mkdir
建立一个目录
语法
bool mkdir(string pathname[,int mode[,bool recursive[,resource context]]])
eg
mkdir(“ljt/newfolder”);
unlink
删除文件
语法
int unlink(string filename);
eg
unlink(”abc.txt”);
3、日期与时间函数
data
返回指定格式的当地时间/日期
语法
string date(string format[,int timestamp])
eg
$time =date(“Y-m-d g:i:s”);
getdate
取得日期与时间的信息
语法
array getdata([int timestamp])
eg
$now=getdate();
$year=$now[“year”];
$month=$now[“month”];
gettimeofday
取得目前的时间（包括格林尼治时间）
语法
array gettimeofday(void)
eg
$time=gettimeofday();
4、字符串处理函数
explode
根据指定的分隔符将字符串拆分成一个数组
语法
array explode(string separator,string string[,int limit])
eg
$str=”a,b,c”;
$res=explode(“,”,$str);//$res[0]=a
implode
将数组内容连接成一个字符串
语法
string implode(string glue,array pieces)
eg
$newarray=array(‘a','b','c');
$res=implode(“,”,$newarray);//$res=a,b,c
strlen
取得字符串的长度
语法
int strlen(string string)
eg
strlen(“www.gxnu.edu.cn”);//传回15
substr
取得字符串指定的某部分字符（子字符串）
语法
string substr(“www.gxnu.edu.cn”,1,7); //返回”ww.gxnu”
5、数学函数库
ceil
将浮点数的小数部分无条件进位
语法
float ceil(float value)
eg
echo ceil(9.99);//返回10
echo ceil(9.12);//返回10
cos
取得浮点数值的余弦值
语法
float cos(float arg)
eg
$numcos=cos(0.5);
floor
将浮点数的小数部分无条件去掉
语法
float floor(floor value)
eg
echo floor(9.12);//返回9
echo floor(9.99);// 返回9
rand
产生一个范围的随机数值
语法
int rand([int min,in max])
eg
$num=rand(0,100);//产生一个介于1到100间的随机数值
round
将浮点数的小数部分四舍五入进位
语法
float round(float value)
eg
float round(9.99)//返回10
float round(9.12)//返回9
sin
取得浮点数值的正弦值
语法
float sin(float arg)
eg
$numsin=sin(0.5);
6、Session函数
session_register
说明一或多个Session里的变量
语法
bool session_register(mixed name[,mixed...])
eg
$name=”flag”;
session_register(“name”);
session_start
初始化Session 信息
语法
bool session(void)
eg
session_start();
7、数组函数
count
计算数组中共有几个数组函数
语法
int count(mixed var[,int mode])
eg
count($array);
list
将数组中的元素值分配给变量
语法
void list(mixed varname,mixed...)
eg
$array=array(a,b,c);
list($str1,$str2,$str3)=$array;//$str1=a
range
建立一个在指定范围内的数组
语法
array range(int low,int high[,int step])
eg
$array=array(0,9);
shuffle
将数组中的元素重新随机排序
语法
bool shuffle(array array)
eg
shuffle($array);