2. Outline o What is String ? o Basic String o Using String As Arrays o Transforming String o Comparing Strings o Searching Strings o Matching Against Mask o String Replace o Other String Function o Arrays Functions

3. What is String ? o A string is series of characters, where a character is the same as a byte. This means that PHP only supports a 256-character set, and hence does not offer native Unicode support. See details of the string type. o A string literal can be specified in four different ways: single quoted double quoted heredoc syntax nowdoc syntax (since PHP 5.3.0)

4. Basic Strings  String objects are a special type of container, specifically designed to operate with sequences of characters.  A string variable is used to store and manipulate text.  String variables are used for values that contain characters.

5. Basic Strings  We using the string to display some notation.  The string, like a variable, will have to be created first. There are two ways to use a string in PHP - you can store it in a function or in a variable. In the example below, we will create a string twice - the first time storing it in a variable, and the second time - in a function, in our case - an echo.

6. Basic Strings <?php $myString = "This is a string!"; echo "This is a string!"; echo $myString; ?>

7. string  Use some different functions & operators to manipulate the string.

8. Using String As Arrays  You can access the individual characters of a strings as if they were members of an array.  $text = “abcdef”; abcdef 012345 Characters Index

9. Using String As Arrays <?php $str = “abcdef”; echo $str[‘1’] ; // b //Or for($i =0 ;$i < srtlen($str); $i++) { echo $str[$i]; } ?>

10. String Function  In PHP we have tow type of functions : 1) User-defined Function. 2) Built-in Function.  User-defined Function : is the function created by user.  Built-in Function : is the function created by PHP, and ready to use.  The real power of PHP comes from its functions.  We just talk about Built-in Function in this chapter

11. Transforming String  If given two arguments, the second should be an array in the form array('from' => 'to',...). The return value is a string where all the occurrences of the array keys have been replaced by the corresponding values. The longest keys will be tried first. Once a substring has been replaced, its new value will not be searched again. string strtr ( string $str, array $replace_pairs )

12. Transforming String <?php echo strtr("Hilla Warld","ia","eo"); ?> Output : Hello World

13. Transforming String  The strtr() If given three arguments, this function returns a copy of str where all occurrences of each (single-byte) character in from have been translated to the corresponding character in to, i.e., every occurrence of $from[$n] has been replaced with $to[$n], where $n is a valid offset in both arguments.; string strtr ( string $str, string $from, string $to )

14. Transforming String "Hi", "world" => "earth"); echo strtr("Hello world",$arr); ?> Output : Hi earth

15. Comparing Strings  You can comparison between strings by more than one method,the PHP when comparison it make convert the data type to other if the data type not the same.

16. Comparing Strings <?php If(“123aa” == 123) { echo “done”; } ?>

17. Comparing Strings  This comparison is case sensitive.  Returns 0 if str1 is greater than str2, and 0 if they are equal. int strcmp ( string $str1, string $str2 )

18. Comparing Strings <?php echo strcmp("Hello world!","Hello world!"); ?> Output : 0

19. Comparing Strings  Binary safe case-insensitive string comparison.  Returns 0 if str1 is greater than str2, and 0 if they are equal. int strcasecmp ( string $str1, string $str2 )

20. Comparing Strings <?php $var1 = "Hello"; $var2 = "hello"; if (strcasecmp($var1, $var2) == 0) { echo '$var1 is equal to $var2 in a case- insensitive string comparison'; } ?>

21. Comparing Strings-example <?php $str = "Ali"; if(strcmp($str, "ali") == 0) { //we won't get here, becuse of case sensitivity } if(strcasecmp($str, "ali") == 0) { we well get here becuse strcasecmp() is case-insensitive } ?>

22. Comparing Strings-example <?php $st1 = “abcd1234”; $st2 = “abcd5678”; echo strncasecmp ($st1,$st2,4); ?>

23. Searching Strings Find the numeric position of the first occurrence of needle in the haystack string. Returns the position of where the needle exists relative to the beginning of the haystack string (independent of offset). Also note that string positions start at 0, and not 1. Returns FALSE if the needle was not found. int strpos ( string $haystack, $needle [, int $offset = 0 ] )

24. Searching Strings <?php echo strpos("Hello world!","wo"); ?> Output : 6

25. Searching Strings-Example <?php $str =“abcdef”; $se_str = “abc”; If(strpos($str,$se_srt) !== false) { echo “found”; } ?>

26. Searching Strings-Example <?php $str ='1234567'; $se_str = '123'; echo strpos($str,$se_str,1); //false ?>

27. Searching Strings-Example <?php $str ='123456'; $se_str = ‘34'; echo strtr($str,$se_str,1); // 3456 ?>

28. Matching Against Mask  Finds the length of the initial segment of subject that contains only characters from mask.  If start and length are omitted, then all of subject will be examined. If they are included, then the effect will be the same as callingstrspn(substr($subject, $start, $length), $mask) (see substr for more information). int strspn ( string $subject, string $mask [, int $start [, int $length ]] )

29. Matching Against Mask <?php echo strspn("Hello world!","kHlleo"); ?> Output : 5

30. Matching Against Mask  Returns the length of the initial segment of str1 which does not contain any of the characters in str2.  Returns the length of the initial segment of subject which consists entirely of characters in mask. int strcspn ( string $str1, string $str2 [, int $start [, int $length ]] )

31. Matching Against Mask <?php echo strcspn("Hello world!","w"); ?> Output : 6

32. String Replace  This function returns a string or an array with all occurrences of search in subject replaced with the given replace value.  This function returns a string or an array with all occurrences of search in subject (ignoring case) replaced with the given replace value.  eplaces a copy of string delimited by the start and (optionally) length parameters with the string given inreplacement. str_replace ( $search, $replace, $subject [, int &$count ] ) str_ireplace ( $search, $replace, $subject [, int &$count ] ) substr_replace ( $string, $replacement, $start [, $length ] )

33. String Replace-example <?php echo str_raplace(“Mr”,”Welcom”,”Mr Ali”); ?> Welcom Ali

34. String Replace -exmple <?php $a = 0; echo str_raplace(“a”,”b”,”a1a1a1”,$a); echo $a // 3 ?>

35. String Replace -exmple <?php echo substr_replace("welecom ali ","hi",7); echo “ ”; echo substr_replace("welecom my brother ali ","mr",9,10); ?> welecomhi welecom mmrali

36. String Replace -exmple <?php $str = “123456789”; echo substr($str,0,3);//123 echo substr($str,1,1);//2 echo substr($str,-2);//89 echo substr($str,-2,1);//8 ?>

37. String Functions strtoupper() - Make a string uppercase strtolower() - Make a string lowercase ucfirst() - Make a string's first character uppercase ucwords() - Uppercase the first character of each word in a string

38. strtoupper() <?php $str = “make a string uppercase "; $str = strtoupper($str); echo $str; ?> MAKE A STRING UPPERCASE

39. strtolower() <?php $str = “MAKE A STRING LOWERCASE "; $str = strtolower($str); echo $str; ?> make a string lowercase

40. ucfirst() <?php $str = “make a string's first character uppercase "; $str = ucfirst($str); echo $str; ?> Make a string's first character uppercase

41. ucwords() <?php $str = “uppercase the first character of each word in a string "; $str = ucwords($str); echo $str; ?> Uppercase The First Character Of Each Word In A String

42. str_replace() <?php echo str_replace("world","Peter","Hello world!"); ?> Hello Peter!

43. str_replace() <?php $arr = array("blue","red","green","yellow"); print_r(str_replace("red","pink",$arr,$i)); echo "Replacements: $i"; ?> Array ( [0] => blue [1] => pink [2] => green [3] => yellow ) Replacements: 1

44. wordwrap()  Wraps a string to a given number of characters using a string break character.  Returns the given string wrapped at the specified length.

45. wordwrap() <?php $text="The quick brown fox jumped over the lazy dog."; echo wordwrap($text,20," \n"); ?>

46. str_split ()  Converts a string to an array.  If the optional split_length parameter is specified, the returned array will be broken down into chunks with each being split_length in length, otherwise each chunk will be one character in length.  FALSE is returned if split_length is less than 1. If the split_length length exceeds the length of string, the entire string is returned as the first (and only) array element. array str_split ( string $string [, int $split_length = 1 ] )

47. str_split () <?php $str = "Hello Friend"; $arr1 = str_split($str); $arr2 = str_split($str, 3); print_r($arr1); print_r($arr2); ?>

48. str_word_count()  Specify the return value of this function. The current supported values are:  0 - returns the number of words found  1 - returns an array containing all the words found inside the string  2 - returns an associative array, where the key is the numeric position of the word inside the string and the value is the actual word itself str_word_count ( string $string [, int $format = 0 [, string $charlist ]] )

49. str_word_count()

50. explode ()  Returns an array of strings, each of which is a substring of string formed by splitting it on boundaries formed by the string delimiter. array explode ( string $delimiter, string $string [, int $limit ] )

51. explode () <?php // Example 1 $chars = “A B C D E F"; $pieces = explode(" ", $chars); echo $pieces[0]; // A echo $pieces[1]; // B ?>

52. strrev()  Returns string, reversed. <?php echo strrev("Hello world!"); // outputs "!dlrow olle ?>

53. str_shuffle ()  shuffles a string. One permutation of all possible is created.

54. str_shuffle () <?php $str = 'abcdef'; $shuffled = str_shuffle($str); // This will echo something like: bfdaec echo $shuffled; ?>

55. rand ()  If called without the optional min, max arguments rand() returns a pseudo-random integer between 0 and getrandmax(). If you want a random number between 5 and 15 (inclusive), for example, use rand(5, 15) int rand ( void ) int rand ( int $min, int $max )

56. rand () <?php echo rand(). "\n"; echo rand(). "\n"; echo rand(5, 15); ?>

57. round () <?php echo round(3.4); // 3 echo round(3.5); // 4 echo round(3.6); // 4 echo round(3.6, 0); // 4 echo round(1.95583, 2); // 1.96 echo round(1241757, -3); // 1242000 echo round(5.045, 2); // 5.05 echo round(5.055, 2); // 5.06 ?> round ( float $val [, int $precision = 0 [, int $mode = PHP_ROUND_HALF_UP ]] )

58. round () <?php echo round(9.5, 0, PHP_ROUND_HALF_UP); // 10 echo round(9.5, 0, PHP_ROUND_HALF_DOWN); // 9 echo round(9.5, 0, PHP_ROUND_HALF_EVEN); // 10 echo round(9.5, 0, PHP_ROUND_HALF_ODD); // 9 echo round(8.5, 0, PHP_ROUND_HALF_UP); // 9 echo round(8.5, 0, PHP_ROUND_HALF_DOWN); // 8 echo round(8.5, 0, PHP_ROUND_HALF_EVEN); // 8 echo round(8.5, 0, PHP_ROUND_HALF_ODD); // 9 ?>

59. max()  If the first and only parameter is an array, max() returns the highest value in that array. If at least two parameters are provided, max()returns the biggest of these values. max ( array $values ) max ( $value1, $value2 [, $value3... ] )

60. max()  max() returns the numerically highest of the parameter values. If multiple values can be considered of the same size, the one that is listed first will be returned.  When max() is given multiple arrays, the longest array is returned. If all the arrays have the same length, max() will use lexicographic ordering to find the return value.  When given a string it will be cast as an integer when comparing.

61. max()

62. min()  If the first and only parameter is an array, min() returns the lowest value in that array. If at least two parameters are provided, min() returns the smallest of these values.  min() returns the numerically lowest of the parameter values. min ( array $values ) min ( $value1, $value2 [, $... ] )

63. min() ?php echo min(2, 3, 1, 6, 7); // 1 echo min(array(2, 4, 5)); // 2 echo min(0, 'hello'); // 0 echo min('hello', 0); // hello echo min('hello', -1); // -1 ?>

64. str_pad ()  This functions returns the input string padded on the left, the right, or both sides to the specified padding length. If the optional argument pad_string is not supplied, the input is padded with spaces, otherwise it is padded with characters from pad_string up to the limit.  Returns the padded string. string str_pad ( string $input, int $pad_length [, string $pad_string = " " [, int $pad_type = STR_PAD_RIGHT ]] )

65. str_pad () <?php $input = "Alien"; echo str_pad($input, 10); // produces "Alien " echo str_pad($input, 10, "-=", STR_PAD_LEFT); // produces "-=-=-Alien" echo str_pad($input, 10, "_", STR_PAD_BOTH); // produces "__Alien___" echo str_pad($input, 6, "___"); // produces "Alien_“ ?>

66. str_repeat ()  Returns input repeated multiplier times. <?php echo str_repeat("-=", 10); ?> string str_repeat ( string $input, int $multiplier )

67.  Array Functions

68. array_push()  array_push () Push one or more elements onto the end of array  Returns the new number of elements in the array. int array_push ( array &$array, $var [, mixed $... ] )

69. array_push() <?php $stack = array("orange", "banana"); array_push($stack, "apple", "raspberry"); print_r($stack); ?>

70. array_push()  array_pop — Pop the element off the end of array  Returns the last value of array. If array is empty (or is not an array), NULL will be returned. array_pop ( array &$array )

71. array_pop() <?php $stack = array("orange", "banana", "apple", "raspberry"); $fruit = array_pop($stack); print_r($stack); ?>

72. array_merge()  array_merge — Merge one or more arrays  Merges the elements of one or more arrays together so that the values of one are appended to the end of the previous one. It returns the resulting array.  If the input arrays have the same string keys, then the later value for that key will overwrite the previous one. If, however, the arrays contain numeric keys, the later value will not overwrite the original value, but will be appended.  Values in the input array with numeric keys will be renumbered with incrementing keys starting from zero in the result array.  Returns the resulting array. array array_merge ( array $array1 [, array $... ] )

73. array_merge() "red", 2, 4); $array2 = array("a", "b", "color" => "green", 4); $result = array_merge($array1, $array2); print_r($result); ?>

74. array_rand ()  array_rand — Pick one or more random entries out of an array  Picks one or more random entries out of an array, and returns the key (or keys) of the random entries.  If you are picking only one entry, array_rand() returns the key for a random entry. Otherwise, it returns an array of keys for the random entries. This is done so that you can pick random keys as well as values out of the array. array_rand ( array $input [, int $num_req = 1 ] )

75. array_rand () <?php $bmw = array(“X2", “X3", “X4", “X5", “X6"); $rand_keys = array_rand($bmw, 2); echo $bmw[$rand_keys[0]]. "\n"; echo $bmw[$rand_keys[1]]. "\n"; ?

76. array_replace ()  array_replace — Replaces elements from passed arrays into the first array  array_replace() replaces the values of the first array with the same values from all the following arrays. If a key from the first array exists in the second array, its value will be replaced by the value from the second array. If the key exists in the second array, and not the first, it will be created in the first array. If a key only exists in the first array, it will be left as is. If several arrays are passed for replacement, they will be processed in order, the later arrays overwriting the previous values.  array_replace() is not recursive : it will replace values in the first array by whatever type is in the second array.  Returns an array, or NULL if an error occurs. array array_replace ( array $array, array $array1 [, array $... ] )

77. array_replace () "pineapple", 4 => "cherry"); $replacements2 = array(0 => "grape"); $basket = array_replace($base, $replacements, $replacements2); print_r($basket); ?>

78. range ()  range — Create an array containing a range of elements  Returns an array of elements from start to limit, inclusive. array range ( mixed $start, mixed $limit [, number $step = 1 ] )

79. range ()

80. shuffle ()  This function shuffles (randomizes the order of the elements in) an array.  Returns TRUE on success or FALSE on failure. bool shuffle ( array &$array )

81. shuffle () <?php $numbers = range(1, 20); shuffle($numbers); foreach ($numbers as $number) { echo "$number "; } ?>

82. asort ()  asort — Sort an array and maintain index association  This function sorts an array such that array indices maintain their correlation with the array elements they are associated with. This is used mainly when sorting associative arrays where the actual element order is significant.  Returns TRUE on success or FALSE on failure. bool asort ( array &$array [, int $sort_flags = SORT_REGULAR ] )

83. asort () "lemon", "a" => "orange", "b" => "banana", "c" => "apple"); asort($fruits); foreach ($fruits as $key => $val) { echo "$key = $val\n"; } ?>

84. usort ()  usort — Sort an array by values using a user-defined comparison function  This function will sort an array by its values using a user-supplied comparison function. If the array you wish to sort needs to be sorted by some non-trivial criteria, you should use this function.  Returns TRUE on success or FALSE on failure. bool usort ( array &$array, callable $cmp_function )

85. usort () $value) { echo "$key: $value\n"; } ?>

86. ksort ()  Sorts an array by key, maintaining key to data correlations. This is useful mainly for associative arrays.  Returns TRUE on success or FALSE on failure. bool ksort ( array &$array [, int $sort_flags = SORT_REGULAR ] )

87. ksort () "lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple"); ksort($fruits); foreach ($fruits as $key => $val) { echo "$key = $val\n"; } ?>

88. array_fill ()  Fills an array with num entries of the value of the value parameter, keys starting at the start_index parameter.  Returns the filled array. array array_fill ( int $start_index, int $num, mixed $value )

89. array_fill() <?php $a = array_fill(5, 6, 'banana'); $b = array_fill(-2, 4, 'pear'); print_r($a); print_r($b); ?>