String processing of PHP learning notes

Blog posted on 2016 0531.11:30

Handling of strings

A summary of some of the methods that may be used is mainly:

First common words

1.strlen () string length

$a = "HI"; echo strlen ($a);

The result is 2.

2.STRCMP () string comparison, case-sensitive, same return 0

Var_dump (strcmp ("Hello", "Hello")); The result is int1.

Var_dump (strcmp ("A", "B")); The result is int-1.

3,STRCASECMP () string comparison, case insensitive, same return 0,

Echo strcasecmp ("A", "a"); The returned result is int 0

4. Strtolower () Turn lowercase

$a =app

echo strtolower ($a); The result is an app

5,strtoupper () Turn capital,

echo strtoupper ($a);

Ditto for the opposite meaning

6.explode () split string, split into array (returns an array)

$a = "N01XN02XN03XN04;"

$attr =explode ("x", $a); X is a separator

Var_dump ($ATTR);

The result is:

Array (size=4)

0=>string ' No1 ' (lenght=3)

1=>string ' NO2 ' (lenght=3)

2=>string ' NO3 ' (lenght=3)

3=>string ' No4 ' (lenght=3)

* The use of the more common

Example database 1 content Lookup

2 answers to the question selection questions

7,implode () stitching array elements into a string

$a = "N01/n02/n03/n04"

Implode (">", $attr)

The result is n01>n02>n03>n04.

8. Substr_replace (string,replacement,start,length) * Replace string, replace specified position

Substr_replace ($a, "xx", 0,4) replaces the contents of the specified position with "XX"

9 Str_replace (find,replace,string) replaces some characters in a string with other characters

Find replacements

Echo Str_replace ("n", "M", $a);

Replace All "n" in $ A with "M"

Ten substr () intercept characters

Subsre ($a, 0,4) intercepts characters from $ A 0 in length lenght=4

$STR = array

(

Array ("n001", "Han"),

Array ("n002", "Hui"),

Array ("n003", "Miao")

);

$a = "n001^ han |n002^ hui |n003^ miao Nationality |";

Echo substr ($a, 0,strlen ($a)-1);

Regular expressions

Arrays and data structures in PHP

String processing of PHP learning notes