Windows Phone Application Development Core Technologies of PHP and Mysqlweb Application Development Part 1 Php Basics-1 Start to Understand PHP

1.1 The first php

Copy the code The code is as follows:

< body>
echo "Hello Everybody!";
?>

Additional: Usage of phpinfo() function
1.2 Enter the php script
1.2. 1 Mark PHP code paragraphs
1.2.2 Statements and comments
/* */
//
#
#
1.2.3 Mixing PHP and HTML
1.3 How to store data
1.4 Enter the basic data type of PHP
1.4.1 Number : (Integer (int) and floating point number (float)) Octal indicates that the number must be preceded by 0 (zero), and hexadecimal indicates that the number must be preceded by 0x.
Note: 1 When operating with floating point numbers, only approximate values ​​will be taken
2 5/2＝2.5 If you want to get an integer, use the round() function
1.4.2 String
Single quotes: ' ', in order to include single quotes in the string, Just precede it with a backslash.
The simplest way to define a string is to surround it with single quotes (punctuation mark ').
If you want to output a single quote, you need to add a backslash () in front of it. To output a backslash before a single quote or at the end of a string, enter two (\)
Note that if a backslash is added before any other character, the backslash will be output directly.
Double quotes " "
Escaped characters Meaning
n Line feed (LF or 0x0A (10) in ASCII)
r Carriage return (CR or 0x0D (13) in ASCII)
t Horizontal tab (HT or 0x09 ( 9) in ASCII)
v vertical tab (VT or 0x0B (11) in ASCII) (since PHP 5.2.5)
f page feed (FF or 0x0C (12) in ASCII) (since PHP 5.2.5)
\ backslash
$ dollar mark
" double quotation mark
[0-7]{1,3} The string that matches the sequence of this expression is an octal character
x[0-9A-Fa-f]{ 1,2} The string that matches the sequence of this expression is a hexadecimal character
1.5 Some very useful functions
1.5.1 nl2br: Insert html newline character after each new line (n) in the string

Copy the code The code is as follows:

echo nl2br("foo isn'tn bar");
?>

1.5.2 var_dump: View types and variable values
1.5 .3 print_r: Returns the result to a string instead of outputting the result to the output stream. This user-friendly output is especially useful for objects and arrays
print_r() displays easy-to-understand information about a variable. If a string, integer or float is given, the variable value itself will be printed.
If an array is given, the keys and elements will be displayed in a certain format.
1.5.4 var_export: It is similar to var_dump. , except that its output is actually a valid php code representation of the provided data value

Copy the code The code is as follows:

$arr=array(1,2,3, 4);
var_exprot($arr);
?>

The above introduces the core technologies of Windows Phone application development PHP and Mysqlweb application development Part 1 Php Basics-1 Start to understand PHP, including the content of Windows Phone application development. I hope it will be helpful to friends who are interested in PHP tutorials.