Php study notes [pre-defined array (ultra-Global Array)]

Php learning notes pre-defined array (ultra-global array). For more information, see.

Php learning notes pre-defined array (ultra-global array). For more information, see.

1.  
2.  
3. /* Pre-defined array:
4. * Automatic global variable --- Super Global Array
5. *
6. * 1. contains data from WEB servers, clients, runtime environments, and user input.
7. * 2. These arrays are special.
8. * 3. These arrays can be used directly if they take effect automatically within the global range.
9. * 4. users cannot customize these arrays, but these arrays are operated in the same way as their own arrays.
10. * 5. You can directly use these arrays in functions.
11. *
12. * $ _ GET // variable submitted to the script through URL request
13. * $ _ POST // variables submitted to the script through the http post method
14. * $ _ REQUEST // variables submitted to the script through GET, POST, and COOKIE mechanisms
15. * $ _ FILES // variables submitted to the script by uploading FILES via the http post method
16. * $ _ COOKIE
17. * $ _ SESSION
18. * $ _ ENV // variables submitted to the script in the execution environment
19. * $ _ SERVER // The variable is set by the web server or directly associated with the execution environment of the current script.
20. * $ GLOBALS // as long as the variables are valid for the current script, the array key name is the name of the global script.
21. *
22. *
23. */
24. // The Super Global array can be directly called within the function.
25. $ Arr = array (10, 20); // A general array
26. $ _ GET = array (50, 90); // A Super Global array
27. Function demo (){
28. Global $ arr; // you must include
29. Print_r ($ arr );
30. Print_r ($ _ GET); // You do not need to include a directly called ultra-global array.
31. }
32. ?>
34.  
35. // Directly use the passed value as a variable, which is useful when register_global = on is in the php. ini configuration file.
36. Echo $ username ."
    ";
37. Echo $ email ."
    ";
38. Echo $ page ."
    ";
39. // The most stable value method
40. Echo $ _ GET ["username"]."
    ";
41. Echo $ _ GET ["email"]."
    ";
42. Echo $ _ GET ["page"]."
    ";
43. ?>
44. "Demo. php? Username = zhangsan & email = aaa@bbb.com & page = 45 "> this is a $ _ GET test
46. "Demo. php" method = "post">
47. Username: "Text" name = "uname"/>
    
48. Password: "Password" name = "pass"/>
    
49. "Submit" value = "login"/>
51.  
52. Print_r ($ _ GET); // cannot receive
53. Print_r ($ _ POST); // to receive
54. ?>
55.  
56. // $ _ ENV usage
57. Echo'

    ';   

    • Print_r ($ _ ENV );
      • Echo'
      • ';
      • // Display the current environment
      • // You can also traverse
      • ?>
      •  
      • // Use the $ GLOBALS ultra-global array to call global variables within the function
      • $ A = 100;
      • $ B = 200;
      • $ C = 300;
      • Function demo ()
      • {
      • // Directly call global variables
      • Echo $ GLOBALS ["a"]."
        ";
      • Echo $ GLOABLS ["B"]."
        ";
      • Echo $ GLOABLS ["c"]."
        ";
      • }
      • ?>