3. Write a program to remotely crawl the content of the http://bbs.it-home.org/search?q=php web page, match all hyperlink addresses in the web page, and write it into url.txt 2. Mysql part: 1. How to check the efficiency index usage of SQL statements? js part: How to change the form's action to ?do=login_bak? when the age value is filled in as 18Server part: 1. What is the command to check the current server load? 2. How to check the total number of links to port 1111 of the current server? 3. How to list how many processes containing the name apache are in the current process? Others: We need to build a picture management system. About uploading user pictures. How to avoid 1. Pictures being stolen. 2. Pictures are uploaded repeatedly. How to set the image upload saving directory? Will regular expressions be used to match image addresses? 3. Subtitle part: 1. What is the difference between include and require? The difference lies in how they handle failure. If the required file is not found, a fatal error will occur and the script will stop executing. If the include file is not found, a warning will be displayed, but the script will continue to execute. 2. A variable is assigned a value of 0123, but the output value of the variable is always another number. What is the problem? The PHP interpreter treats numbers starting with 0 as octal, so its value will become octal. 3. How to define a constant in PHP? Through the define() instruction, for example: define("MYCONSTANT", 100) 4. How to transfer a variable by value? You can add & in front of the variable like C++, for example: $a = &$b 5. Can string “10″ and integer 11 be compared in PHP? Yes, PHP’s internal implementation will convert everything to integers, so the numbers 10 and 11 can be compared 6. Under what circumstances is it necessary to use endif to end a conditional statement? When the if statement is followed by a colon ":" instead of braces {, you need to use endif to end the conditional statement |