A simple comparison between PHP and Java syntax

Recently a friend ready to go from Java to PHP, to help her write a simple introduction to PHP, simply tell the difference between Java and PHP.

PS. Ueditor is not going to work----just look at it.

	PHP	Java
file format	<%%> or <%php%> The code is contained inside the Save as . php file	write directly Save as . Java file
language Type	Instant Compile execution	Static compilation Execution
Notes	PHP exclusive # This is also a single-line comment the same point as Java: //&NBSP; This is a single-line comment This is a multiline comment block multiline */
variable naming	PHP Exclusive variable to $ The beginning of the symbol, followed by the name of the variable Same as Java: variable names must begin with a letter or underscore variable names cannot start with a number variable names can contain only alphanumeric characters and underscores ( A-Z,0-9 and _) variable names are case sensitive ($y and $Y are two different variables)
	php is a weak type, used directly when needed, Do not declare function test () {   $x = ten;  echo $x; } detailed how to use /http www.w3school.com.cn/php/php_variables.asp	strongly typed, need to declare type and initialize public void Test () {  int x =10;  system.out.println (x); }
Simple Output	echo $x; or var_dump ($x)	System.out.println (x);
Variable Type	strings, integers, floating-point numbers, logic, arrays, objects, NULL. Although PHP does not specify the type in the variable declaration, but there are these types on the mechanism of the language
Normal Array	$goods = Array (" item 1", " item 2"); Use $goods [0], Get " Product 1 " Get Array length echo Count ($goods);	string[] goods = new string[]{ Item 1 "," item 2 "} Use Goods[0], Get " Product 1 " Get Array length System.out.println (goods.length);
Associative Arrays	$goodsInfo = array ("id" = "xxxx", "name" = " product 1", "price" = "20.00"); How to use: $goodsInfo ["id"];	in the Java does not have an associative array in it, you want to implement similar functions only using Map map<string,string> goodsinfo = new hashmap<string,string> (); goodsinfo.put ("id", "xxxx"); goodsinfo.put ("name", " item 1"); goodsinfo.put ("Price", "20.00"); How to use: goodsinfo.get ("id");
Associative array traversal	foreach ($goodsInfo as $key = = $val) { echo " Product attributes: ". $key.", values: ". $val; echo "<br/>"; } Output Result: Product attributes: ID, values: xxxx ... The following ellipsis	for (String Key:goodsInfo.keySet ()) {  string str = String.Format (" Commodity properties: %s, key,goodsinfo.get (key));  system.out.println (str); } output result: value: xxxx
operator	too much, too lazy to write, see for yourself http://www.w3school.com.cn/php/php_operators.asp
Logical Conditions	If If Else If ElseIf Else Switch for while these are the same, there is nothing to say, said a PHP in, and Java not in the Foreach this and JS only applies to arrays, and is used to iterate through each key in the array. / value pairs. for normal arrays foreach ($array as $value) { Direct use of $value } for associative arrays, the example is referenced in the above associative array foreach ($array as $key = = $value) { Direct use of $key and $value }
function	and the JS in the same way, it's not written here and Java the difference.
built-in global variables	PHP mainly used in Web , so there are many global variables built in, and Java used in Request get the same, specific explanations look at the Web page http://www.w3school.com.cn/php/php_superglobals.asp

Recommended books: "PHP in detail"

Recommended Sites: php100

A simple comparison between PHP and Java syntax