PHP Learning with notes 1

 First line break "; Echo"
Second NewLine ';#<<
 <符号定义字符串的方法 #首先设置一个结束符号 #这个符号必须单独放在一个行的行首位置 #不然不能识别 #结束符必须单独一行echo <<
  How are you doing
  
However, it is not good for STD; #数组 $arr 1 = Array (' You ', ' good '); echo "
  
$arr 1[1] ";    $arr 2 = Array (0=> ' n '); echo "
  
$arr 2[0] ";    #常量 define (' Bitch ', 111); echo "
  
". Bitch. $arr 2[0]; #用. To connect the string and the variable echo "
  
". __file__; #php提供了几个常量 This is one of the #变量的作用域 # 1) function inside the scope is the function # 2) Outside the function is the entire PHP but the user-defined function cannot be used # to use must use $heng = '    Ha ';    function Hello () {global $heng; echo "
  
". $heng;    } hello ();    #动态变量 #并不是我想的那样/* $a 1 = 1;    $b 1 = $a 1; echo "
  
". $b 1;    $a 1 = 2; echo "
  
". $b 1;*/$chang _name =" trans "; $trans = ' can see me '; echo "
  
$chang _name----$ $chang _name "; #php内置好多预定义的变量 must be assigned to one of our own defined #变量才能用 reference http://php.net/manual/zh/reserved.variables.php $host = $_server[' http    _host ']; echo "
  
$host "; #字符串运算符 #只有. This operation symbol cannot use the plus sign echo "
  
$a "." $b ";//13 echo"
  
".    ("$a" + "$b");//4 #连接字符 $a. = $b; #相当于 $a = $a. $b; echo "
  
". $a; #逻辑运算 && = and, | | = OR, Xor is true if ($a and $b) {echo '
  
conditions set ";    } #@ Mask Error message $worry = @ (5/0); #php函数 similar to JavaScript function HelloWorld () {echo '
  

  Nihao";    } HelloWorld ();    #引用传值 the same as C + +, the default parameter is $a 10 = 8;    Function Zijia (& $a) {$a + = 10;    } Zijia ($a 10); echo "
  
$a 10 ";    #支持变量函数 the so-called variable function is to call the function using the variable name $func = "HelloWorld";    $func ();    #对函数的引用的就是对函数返回值的应用 function h () {return "HelloWorld";    } $aaaa = h (); echo "
  
". $aaaa;  #声明一个引用类型的函数 #发现引用函数不能直接返回一个常量 #所以 can foresee that it returns a variable #地址 instead of copying a value directly to the Received variable function &hh () {$str =        "HelloWorld";    return $str;    } $bbbb = &hh (); echo "
  
$BBBB "; #当引用结束的时候可以通过unset () to dereference #php命名规范 #类名使用驼峰法 #类属性前面就前缀m #类的方法命名 general rule prefixes such as the is Get Set #变量使用小驼峰命名 #引用变量要有前缀r The global variable has the G prefix static variable using the s prefix #变量分割使用_ #方法, the class does not use the _ but the case is able to #php流程控制语句 and other languages as much as a foreach () #类似于java的增强for循环 #在一个 Complex PHP pages may contain multiple conditional statements, and looping statements #和函数 using {} can be cumbersome, so PHP provides another way to use ":" #代替 "{" and "end*" instead of "}" #支持endif, ENDWHILE,ENDFOR,ENDREAC    H,endswitch $s = 1; echo "
  
"; while ($s + + <): echo "I love you.
  
";    Endwhile; ?>
 

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