PHP commonly used functions ____ functions

PHP Common function Summary mathematical function 1.  ABS (): the absolute value $abs = ABS (-4.2); 4.2 Numeric value Absolute number 2.  Ceil (): Take the whole echo ceil (9.999) in one method; 10 floating-point number into a whole 3.  Floor (): To take the whole echo floor (9.999); 9 floating point number direct shed to the decimal part of 4. Fmod (): floating-point number? 1 2 3 4
$x = 5.7;  $y = 1.3; Two floating-point numbers, x>y floating point remainder $r = Fmod ($x, $y); $r equals 0.5, because 4 * 1.3 + 0.5 = 5.7
5. POW (): Returns the number of N-Second square echo POW (-1, 20); 1 Base Number |n The second square of the value of 6.  Round (): Floating-point number rounded echo round (1.95583, 2); 1.96, a number | Keep the number of digits after the decimal point, the default is 0 rounded results 7.  sqrt (): square root echo sqrt (9); 3 square root 8.  Max (): Max Echo Max (1, 3, 5, 6, 7);  More than 7 digits or arrays return the maximum value of Echo max (Array (2, 4, 5)); 5 9. Min (): Minimum value input: multiple digits or array output: Returns the minimum value of 10.  Mt_rand (): Better random number input: Minimum | Maximum, output: Random number of random returns within the range of the value of Echo mt_rand (0, 9); N 11.  Rand (): Random number input: Min | Maximum, output: Random number of random return range within the value of 12. Pi (): Gets the pi value to go to a space or other character: 13.    Trim (): Remove spaces or other predefined characters at each end of the string? 1 2 $str = "\r\nhello world!\r\n"; echo Trim ($STR);
Input: Target string return value: The string 14 after the purge.    RTrim (): Delete space or other predefined characters to the right of the string? 1 2 $str = "Hello world!\n\n"; echo RTrim ($STR);
Chop (): Alias 16 of RTrim (). LTrim (): Deletes a space or other predefined character to the left of the string
? 1 2 $str = "\r\nhello world!"; Echo LTrim ($STR);
DirName (): Returns the directory part of the path echo dirname ("c:/testweb/home.php"); C:/testweb input: A string return value containing a path: Returns the directory partial string generation and transformation of the file path: 18.    Str_pad (): Fill the string to the specified length? 1 2 $str = "Hello World"; Echo Str_pad ($str, 20, ".");
Enter: the string to fill |  Length of new String | String used for padding, default is blank output: finished string 19.  Str_repeat (): Repeats use of the specified string echo str_repeat (".", 13); String to repeat | The number of times the string will be repeated 13 point 20. Str_split (): Splits the string into an array print_r (Str_split ("Hello"));  Enter: String to split | The length of each array element, the default 1 output: A split string array of 21.  Strrev (): Invert string echo strrev ("Hello world!"); !dlrow Olleh Output: String 22 after the reverse order of the target string.    WordWrap (): Wrap the string in a specified length? 1 2 3
$STR = "An example on a long word is:supercalifragulistic"; Echo WordWrap ($STR, 15);
Input: Target string | Maximum width output: The new string 23 after the line is folded. Str_shuffle (): Randomly disrupts all characters in the string echo str_shuffle ("Hello World"); Input: Target string sequential output: scrambled string 24.    PARSE_STR (): Parse a string into a variable? 1 2 parse_str ("Id=23&name=john%20adams", $myArray); Print_r ($myArray);
Enter the array name output:  The string  |  storage variable to parse:  return array ([id]  =>  23[name]  =>  john&nbsp ; Adams) 25. Number_format ():  to format numbers   input via thousands group number  |  specify how many decimal  |  rules are used as the character   string for the decimal point |   The string output used as the thousand separator:  1,  000,  000  1,  000. 00  1.000. 000,  00 Case conversion: 26. Strtolower ():  string to lowercase echo  strtolower ("hello world!"); Target string   lowercase string 27. The Strtoupper ():  string is converted to uppercase echo  Strtoupper ("hello world!"); Output:  Uppercase string 28. Ucfirst ():  string initial capitalization echo  Ucfirst ("Hello world"); //Hello world 29. Ucwords ():  string The first character of each word to uppercase echo  ucwords ("Hello world"); //Hello world HTML Tag Association: 30. Htmlentities ():  convert a character to an HTML entity   ?    1 2   $str  =  "john &  ' Adams"; echo  htmlentities ($str,  ent_compat); // john &  ' Adams '
Htmlspecialchars (): Predefined words Fu Jing HTML encoding 32. NL2BR (): \ n escaped for < br > tag echo nl2br ("One line.\nanother line."); Output: Processed string 33.strip_tags (): Stripped HTML, XML, and PHP tags echo strip_tags ("Hello < b >world! </B > ");   34.addcslashes (): Add a backslash before the specified character to escape the character in the string? 1 2 3
$str = "Hello, my name is John Adams"; Echo $str; Echo addcslashes ($str, ' m ');
Input: Target string | Specifies a specific character or range of characters 35.stripcslashes (): Deletes the backslash echo stripcslashes ("Hello, \my Na\me is Kai ji\m") added by Addcslashes (). The target string Hello, my name is Kai Jim. 36.addslashes (): Add backslashes before specifying predefined characters $str = "Who's John Adams?"; echo addslashes ($STR); Output: Escaping the ' "\ and null in the target string 37.stripslashes (): Deletes the escape character Echo stripslashes (" Who\ ' John Adams ") added by Addslashes (); Clear escape symbol who ' s John Adams?   38.quotemeta (): Add a backslash before certain predefined characters in the string? 1 2 3
$STR = "Hello World". (Can you hear me?) "; echo Quotemeta ($STR); Hello world\. \ (Can you hear me\?\)
39.CHR ():  returns the character ECHO&NBSP;CHR (052); // ascii  value from the specified  ASCII  value returns the corresponding character 40.ord ():  Returns the ASCII value of the first character of the string Echo ord ("Hello");  string comparison of the first character  ASCII  value string: 41.strcasecmp ():  Case-insensitive comparison of two string echo strcasecmp ("hello world!",  "hello world!"); Enter:  two target string   output:  1 |  0 |  small  - 1 42.strcmp ():  case sensitive comparison two string 43. STRNCMP ():  compares the first n characters of a string,  a case-sensitive call: int strncmp  (string  $str 1 , string   $STR 2 , int  $len) 44.strncasecmp ():  Compare the first n characters of a string,  case-insensitive calls: int  strncasecmp  (string  $str 1 , string  $str 2 , int  $len  ) 45.strnatcmp ():  Natural order method to compare string length,  case-sensitive call: int strnatcmp  (string  $str 1 , string $ str2 ) Enter:  target string 46.strnatcasecmp ():  Natural order method to compare string length,  case-insensitive invocation:  int strnatcasecmp   (string  $str 1 , string  $str2 ) string cutting and stitching: 47.chunk_split () &nbsp: Dividing a string into small chunks:  str chunk_split (str  $body [,int  $len [ ,str  $end]) Enter:  $body target string,  $len length,  $str insert terminator   output:  split strings 48.strtok ():  cut strings Call:  str strtok (str  $str, str  $token) Target string $str, $token for flag cutting returns the cut string 49.explode ():   Use a string to split another string for a flag call:  array explode (str  $sep, str  $str [,int  $limit]) Enter:   $SEP for,  $str the target string,  $limit returns the array contains the maximum number of elements   output:  the array formed after the string was segmented 50.implode ():  with join,   Connect array values to a character string called: string implode  (string  $glue  , array  $pieces   $glue default,  "is directly connected to the 51.SUBSTR ():  intercept string call: string substr  (string  $string    int  $start  [, int  $length  ] ) string lookup replacement: 52.str_replace ():  string substitution operation,  Case-sensitive call Mix str_replace (mix  $search, mix  $replace, mix  $subject [,int  &   $num) Enter the string that the:  $search look for,  $replace the replaced string,  $subject the lookup strings,  & $num   Output:  return the replaced result 53.str _ireplace ()   string substitution operation,  case-insensitive call: mix str_ireplace  (mix  $search  , mix   $replace  , mix  $subject  [, int  &  $count]) Enter the string that the:  $search find,   $replace substituted string,  $subject be searched for strings, & $num   Output:  returns the replacement result 54.substr_count ():  statistics a string,   The number of occurrences in another string calls: int substr_count  (string  $haystack  , string  $needle [,  int  $offset  = 0[, int  $length  ]] ) 55.substr_replace ():  A string in the replacement string is called: mixed substr_replace  by another string (mixed  $string, string  $replacement,  int  $start  [, int  $length  ] ) 56.similar_text ():  returns the number of two identical characters in a string call:  int similar_text (str  $str 1, str  $str 2) Enter:  Two comparison string output:  reshape,  same character number 57. STRRCHR ():  returns a string in theA string called: string strrchr  (string  $haystack  , mixed $) that the last occurrence of the position in another string begins at the end. needle ) 58.strstr ():  returns a string called: string strstr  (string  $str, from the beginning position in another string to the end  string  $needle  , bool  $before _needle ) 59.strchr ():  strstr () alias,  Returns a string call to the end of the first occurrence of a string in another string: string strstr  (string  $haystack  , mixed  $needle  [, bool  $before _needle = false ] ) 60.stristr ():  Returns a string that starts at the end of a string in another string, case-insensitive call: string stristr  (string  $haystack  , mixed   $needle  [, bool  $before _needle = false ] ) 61.strtr ():  Some characters in the conversion string call: string strtr  (string  $str  , string  $from  , string   $to  ) 62.strpos ():  looks for the first occurrence of a character in a string to call: int strpos  (string  $haystack    mixed  $needle  [, int  $offset  = 0 ] ) 63.stripos ():  find the position where a character appears first in a string,  case-insensitive   call:  int  stripos  (string  $haystack  , string  $needle  [, int  $offset  ]  ) 64.strrpos ():  looks for the last occurrence of a character in a string call: int strrpos  (string  $haystack  ,  string  $needle  [, int  $offset  = 0 ] ) 65.strripos ():  Looks for the last occurrence of a character in a string,  case-insensitive call: int strripos  (string  $haystack  , string $ needle [, int  $offset  ] ) 66.strspn ():  returns the substring length   invocation for the first time in the string that conforms to mask:  int  strspn  (string  $str 1 , string  $str 2 [, int  $start  [,  int  $length  ]] ) 67.strcspn ():  returns the length of a string that does not conform to mask in the string: int strcspn  (string   $STR 1 , string  $str 2 [, int  $start  [, int  $length  ]   Input:  $str 1 is queried,  $STR 2 query string, $start the character to start the query, $length is the query length   output:  returns from the start to the first few character string statistics: 68.str_word_count ():  The number of words contained in the statistic string is called:  mix str_word_count (str  $str,  []) Enter:  target string   output:  statistics number 69. strlen ():  statistic string length Int strlen (str  $str) input:  target string   Output:  integer length 70.count_chars ():  Statistics the number of occurrences of all letters in the string (0..255)   Call: mixed count_chars  (string  $string  [, int $ mode ] ) string encoding: 71.md5 ():  string MD5 encoding   ?   1 2   $str  =  "Hello"; ECHO&NBSP;MD5 ($STR);
Array function Array creation: 72.array (): Generate an array? 1 2 $a = array ("Dog", "Cat", "Horse"); Print_r ($a);
An array value or a key => value an array-type variable 73.array_combine (): Generates an array with the value of one array as the key and the other as the value $a 1 = Array ("A", "B", "C", "D"); $a 2 = Array ("Cat", "Dog", "Horse", "Cow"); Print_r (Array_combine ($a 1, $a 2));     $a 1 provides a key, $a 2 provides a composite array of 74.range (): Creates and returns an array containing the specified range of elements.      $number = range (0,50,10); Print_r ($number); Input: 0 is the minimum, 50 is the maximum, 10 is the step output: The composite array 75.compact (): Create an array of variables with the parameters? 1 2 3 4 5 6 $firstname = "Peter"; $lastname = "Griffin"; $age = "38"; $result = Compact ("FirstName", "LastName", "age");   Print_r ($result); A variable or array returns an array of variable names, the value of the variable, or a multidimensional array. will be recursively processed 76