PHP2017 latest version interview questions (with answers)

Seeing that many friends are asking for PHP interview questions, I collected some interview questions for you. These are all the latest questions in 2017. I hope they will help you improve your skills. I also wish you can get into the company you want to work in.

This article collects and analyzes the latest 2017 PHP interview questions in more detail. Share it with everyone for your reference. The details are as follows:

1. Use PHP to print out the time of the previous day in the format of 2006-5-10 22:21:21 (2 minutes)

$ a = date("Y-m-d H:i:s", strtotime("-1 day"));

print_r($a);

2, echo The difference between (), print() and print_r() (3 points)

echo and print are not a function, but a language structure

int print(string $arg), only one parameter

echo arg1,arg2; can output multiple parameters and return void

echo and print can only print out string, not the structure

print_r can print out the structure

For example

$arr ​​= array("key"=>"value");

print_r($arr);

3. Templates that can separate HTML and PHP (1 point)

smarty,phplib

4. What tools are used for version control? ?(1 point)

svn,git,cvs

5. How to achieve string flipping?(3 points)

English :

strrev($a)

Chinese or other text:

Chinese: GB2312, the code is encoded using GB2312

function reverse($str)

{

$ret = "";

len=mbstrwidth(str,"GB2312");

for(i=0;i

{

arr[]=mbsubstr(str, $i, 1, "GB2312");

}

return implode("", array_reverse($arr));

}

print_r(reverse("Hello"));

6. Methods to optimize MYSQL database. (4 points, write more and get more)

Statement aspects:

1 Use index to increase query efficiency

2 Optimize query statements and improve index hit rate

Aspects involved in the database:

1 Construct sub-databases and tables to improve the storage and expansion capabilities of the database

2 Use different storage engines as needed

7. The meaning of PHP (send 1 point)

Hypertext Preprocessing Language

Hypertext PreProcessor

8 , What is the function for MYSQL to obtain the current time?, and the function for formatting the date is (2 points)

CURRENT_TIMESTAMP()

DATE_FORMAT()

select DATE_FORMAT("2011- 11-21 10:10:10", "%Y-%m-%d");

9. Method to intercept Chinese text strings without garbled characters. (3 points)

mb_substr($str, 1, 1, "GB2312");

10. Have you ever used version control software? If so, have you used it? What is the name of the version control software? (1 point)

svn

git

11. Have you ever used a template engine? If there is a template engine you use, what is the name? (1 point)

smarty

12. Please briefly describe your most proud development work ( 4 points)

XXX

13. For websites with large traffic, what method do you use to solve the traffic problem? (4 points)

1 Effectively use cache to increase cache hit rate

2 Use load balancing

3 Use CDN to store and accelerate static files

4 Ideas to reduce database Use

5 Check where the bottleneck of statistics is

14. Use PHP to write the code to display the client IP and server IP 1 point)

$_SERVER["REMOTE_ADDR"]

$_SERVER["SERVER_ADDR"]

15. What is the difference between the statement include and require ?To avoid including the same file multiple times, you can use (?) statements to replace them? (2 points)

When it fails:

include generates a warning, while require generates a direct error interrupt

require is loaded before running

include is loaded at runtime

require_once

include_once

16. How to modify the survival time of SESSION (1 minute).

session_set_cookie_params

17. There is a web page address, such as the homepage of the PHP Research Laboratory : http://www.jb51.net/index.html, how to get its content? ($1 point)

file_get_contents

curl

18. In HTTP 1.0, the meaning of status code 401 is (?); if the prompt "File not found" is returned, the header function can be used, and its statement is (?); (2 points)

Unauthorized

header("HTTP/1.0 404 Not Found");

fast CGI:

header("Status : 404 Not Found");

19. In PHP, heredoc is a special string, and its end mark must be? (1 point)

Appear in pairs

$a =

good test

EOD;

20. Talk about asp , Advantages and disadvantages of php and jsp (1 point)

asp needs to rely on IIS and is a language developed by Microsoft

php and jsp can rely on other servers such as apache or nginx

21. Talk about your understanding of mvc (1 point)

model: data structure layer

view: display

control: Receive and judge the input

#22. Write the SQL of the names of the ten people with the most posts. Use the following table: members(id,username,posts,pass,email )(2 minutes)

select top 10 id,username from members order by posts desc

23. Please explain the difference between passing values ​​and passing references in PHP. When to pass by value and when to pass by reference? (2 points)

& means passing by reference

Passing the parameter by reference in the function will change the parameter

Generally in the output parameter When there are more than one, you can consider using references

24. What is the function of error_reporting in PHP? (1 point)

Set the display level of error

25. Please write a function to verify whether the format of the email is correct (2 points)

$str = "jianfeng @126.com";

regex="([a−z0−9\.−]+)@([\da−z\.−]+)\.([a−z\. ]2,6)" ; //Regular

return preg_match(regex,str)

26. Briefly describe how to get the current execution script path, including the obtained parameters . (2 points)

$argc --Get the number of parameters

$argv --Get the parameter list

27. How to modify SESSION The survival time. (1 point)

session_set_cookie_params

28. What is the function of the JS form pop-up dialog box? What is the function of getting the input focus? (2 points)

alert()

confirm()

promote()

focus()

29. What is the redirection function of JS? How to introduce an external JS file? (2 points)

window.location.href="#"

30. What is the difference between foo() and @foo()? (1 point)

@represents all warnings and is ignored

31. How to declare a class named "myclass" without methods and attributes? (1 point)

class myclass

{

}

32. How to instantiate an object named "myclass"? (1 point)

$myclass = new myclass( );

33. How do you access and set the attributes of a class? (2 points)

class A

{

public $name = "A";

}

$a = new A();

n=a-> ;name;

print_r($n);

34, what is between mysql_fetch_row() and mysql_fetch_array Difference? (1 point)

mysql_fetch_array() is an extended version of mysql_fetch_row(). In addition to storing data in an array as a numerical index, you can also store data as an associative index, using the field name as the key.

mysql_connect("localhost", "mysql_user", "mysql_password") or

die("Could not connect: " . mysql_error()) ;

mysql_select_db("mydb");

$result = mysql_query("SELECT id, name FROM mytable");

while (row =mysqlfetcharray(result, MYSQL_ASSOC)) {

printf ("ID: %s Name: %s", row["id"],row["name"]);

}

mysql_free_result($result);

##35. What is the GD library used for? ( 1 point)

Dynamic open image processing library

36. Point out some ways to enter a piece of HTML code in PHP. (1 point)

echo "{html}"

echo {html}

EOD;

37. Which of the following functions can open a file for reading and writing? (1 point) c

(a) fget() (b) file_open() (c ) fopen() (d) open_file()

38. Which of the following options does not add john to the users array? (1 point) b

( a) $users[] = 'john';

(b) array_add($users,'john');

(c) array_push($users,'john');

(d) $users ||= 'john';

39. Will the following program be entered? (1 point) 10

$num = 10;

function multiply(){

num=num * 10;

}

multiply();

echo $num;

?>

40. Use php to write a simple query to find all the people named "Zhang San" Content and print it out (2 points)

Table name UserName Tel Content Date

Zhang San 13333663366 College graduate 2006-10-11

Zhang San 13612312331 Undergraduate graduate 2006-10 -15

Zhang Si 021-55665566 Technical secondary school graduate 2006-10-15

Please complete the code according to the above question:

$mysql_db=mysql_connect("local", "root","pass");

@mysql_select_db("DB",$mysql_db);

$sql = sprintf("select * from %s where UserName = '%s' ",

"Table name",

"Zhang San");

values=mysqlquery(sql);

while(item=mysqlfetchqueryarray( values))

{

echo sprintf("Username: %s, phone number %s, education: %s, graduation date: %s",

item[ 'UserName'],item['Tel'], item['Content'],item['Date']

);

}

41. How to use the following classes and explain what they mean? (3)

class test{

function Get_test($num){

num=md5(md5(num)."En");

return $num;

}

}

$test = new test();

ret=test->Get_test(11);

print_r($ret);exit;

Associate the 32-bit string a1 generated after num is MD5 encoded with "En" and then perform MD5 encoding again

42. Write the format of the SQL statement: insert, update, delete (4 points)

Table name UserName Tel Content Date

Zhang San13333663366 College graduate 2006-10-11

Zhang San 13612312331 Graduated from undergraduate degree 2006-10-15

Zhang Si 021-55665566 Graduated from technical secondary school 2006-10-15

(a) There is a new record (Xiao Wang 13254748547 High school graduate 2007-05-06) Please use SQL statement to add to the table

insert into table name values('Xiao Wang', '13254748547', 'High school graduate', '2007-05-06 ')

(b) Please use sql statement to update Zhang San's time to the current system time

update table name set Date = GETDATE() where UserName = "Zhang San"

(c) Please write to delete all records named Zhang Si

delete from indicates where UserName = "Zhang Si"

##43, Please write down the meaning of the data type (int char varchar datetime text); What is the difference between varchar and char (2 points)

int integer type

char fixed length storage

varchar stores variable length

datetime time

text stores variable length

varchar is variable length

char(20) fixed length

44. MySQ auto-increment type (usually table ID field) must be set to (?) field (1 point)

auto_increment

45. Write the output result of the following program (1 point)

$b=201;

$c=40;

a=b>$c?4:5;

echo $a;

46. Is there a function that detects whether a variable is set? Is it What is the empty function? (2 points)

isset()

empty()

47. What is the function that obtains the total number of query result sets? (1 point)

mysql_num_rows()

48, $arr = array('james', 'tom', 'symfony'); Please print Get the value of the first element (1 point)

print_r($arr[0]);

reset($arr);

print_r(current($arr));

print_r(array_shift($arr));

49. Please use the value of the array in question 41 Separate with ',' signs and merge into string output (1 point)

implode

##50. a='abcdef'; Please take out the value of a And print out the first letter (1 point)

$a[0];

substr($a, 0, 1);

51. Can PHP be connected to databases such as sql server/oracle? (1 point)

Yes

There are ready-made libraries

52. Please write the PHP5 permission control modifier (3 points)

public

private

protected

53. Please write the constructor and destructor of php5 (2 points)

public function construct()

{

}

public function destruct()

{

}

Programming questions:

#1. Write a function to retrieve the file extension from a standard URL as efficiently as possible

For example: http://www.sina.com.cn/abc/de/fg.php?id=1 You need to remove php or .php

$url = "http://www.sina.com.cn/abc/de/fg.php?id=1";

arr=parseurl(url);

pathArr=pathinfo(arr['path']);

print_r($pathArr['extension']);

3. Write a function to calculate the relative paths of two files

For example, $a = '/a/b/c/d/e. php';

$b = '/a/b/12/34/c.php';

The calculated relative path of b relative to a should be http://www. jb51.net/12/34/c.php will add

$a = '/a/b/c/d/e. php';

$b = '/a/b/12/34/c.php';

//Get the relative path of path relative to conpath

function sGetRelativePath(path,conpath)

{

pathArr=explode("/",path);

conpathArr=explode("/",conpath);

$dismatchlen = 0;

for(i=0;i

{

if(conpathArr[i] ! = pathArr[i])

{

dismatchlen=count(pathArr) - $i;

arrLeft=arrayslice(pathArr, $i);

break;

}

}

ret=strrepeat("../",dismatchlen).implode("/", $arrLeft);

return $ret;

}

print_r(sGetRelativePath(b,a));

3. Write a function that can traverse all files and subfolders in a folder.

function aGetAllFile($folder)

{

$aFileArr = array();

if(is_dir($folder))

{

handle=opendir(folder);

while((file=readdir(handle)) != = false)

{

//If it is. or.., skip

if(file=="."||file == ".." )

{

continue;

}

if(is_file(folder."/".file))

{

aFileArr[]=file;

}

else if(is_dir(folder."/".file))

{

aFileArr [file] = aGetAllFile(folder."/".file);

}

}

closedir($handle);

}

return $aFileArr;

}

$path = "/home/test/sql";

print_r(aGetAllFile($path));

The above are the latest interview questions and answers I collected, which will be helpful to everyone.

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Common PHP interview questions and answering techniques in 2017

8 PHP interview questions reflect your understanding of PHP Level

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