Summary and troubleshooting of problems in PHP development_PHP tutorial

Questions in PHP development 1. How to use ord() and intval() functions in PHP?

The ord() function returns the ASCII code value of a character;
For intval(), if the parameter is a string, it returns the character before the first character in the string that is not a number. The integer value represented by the numeric string. If the first character in the string is ‘-’, counting starts from the second character.
If the parameter is a dotted number, its rounded value is returned.
Of course, the value returned by intval() is within the range that can be represented by a 4-byte range (-2147483648~2147483647). Values ​​exceeding this range will be replaced by boundary values;
For example:

1. ord('A')=65;
2. intval("A")=0;
3. intval("1123Asdfka3243")=1123;
4. intval(12.3223)=12; intval("1213423423459348752347598723498572398475")=2147483647; 2398475")=-2147483648;
6. Problem 2 in PHP development. What is the reason for the assignment in condition warning?
This is used in the PHP manual: while ($data = mysql_fetch_assoc($result)) The result was an assignment in condition warning. After inspection, I finally found out that it turned out to be a loose writing method. It's not a mistake. The solution is as follows:

while (($row = mysql_fetch_assoc($result)) != false)

This way there will be no prompts

PHP development Question 3. Form submission to this page?

action followed by the address of this page is as above,

or use $_SERVER['PHP_SELF'] is as follows

Problems in PHP development 4. Print output content function?

echo: Output variables or characters

print_r: Output array

var_dump: Output Boolean value

Problem 5 in PHP development . Convert between Greenwich Mean Time and formatted time?

a) Convert Greenwich Mean Time to specified format time

/**

* Convert timestamp to Greenwich Mean Time
1. *
2. * It is recommended to use the gmdate / date that comes with PHP
*/
4. function UnixToGmt($
5. format_string
=
6. "Y-m-d H:i: s" ,$UnixTime = 0) { return @gmdate($format_string,$UnixTime);
7. }
b) What is the Greenwich Mean Time of the current time?
9. $d1 = date(mktime()) + 28800; //Add the time zone difference of 8 hours
Example:

$d2 = UnixToGmt("Y-m-d H:i :s", $d1); //The current time specifies the format time

echo $d2; //Output

Question 6 in PHP development, get the parameters passed by GET?

For example: http://127.0.0.1/index.PHP?id=3

Get the value of ID: $_GET[id]

http://www.bkjia.com/PHPjc/446136.html

www.bkjia.com

true

http: //www.bkjia.com/PHPjc/446136.html

TechArticleQuestions in PHP development 1. How to use ord() and intval() functions in PHP? The ord() function returns the ASCII code value of a character; for intval(), if the parameter is a string, the first one in the string is returned...