[Introduction] 1. PHP operators PHP has a rich set of operators, most of which come directly from the C language. According to different functions, operators can be divided into: arithmetic operators, string operators, assignment operators, bit operators, conditional operators, and logical operators. There is a rich set of operators in PHP, most of which come directly from the C language. According to different functions, operators can be divided into: arithmetic operators, string operators, assignment operators, bit operators, conditional operators, and logical operators. When various operators are in the same expression, their operations have a certain priority.
(1) Arithmetic operation
+ - * / % ++ --
(2) String operator
String operator only A. (dot) is the English period. It can concatenate strings to form a new string, or it can concatenate strings with numbers, and the types will be automatically converted.
$a="dawanganban"; $b="123"; echo $a.$b; //输出结果:dawanganban123
(3) Assignment operator
= += -= *= /= %= .= $a="dawanganban"; $a.=1; $a.=2; $a.=3; echo $a.$b; //输出结果:dawanganban123
(4) Bit operators
& | ~ ^ >
(5) Comparison operators
> = === !==
: is not equal to sum! =Same
===: Identity, equal values and consistent types
! ==: Non-identity, unequal values or inconsistent types
echo 5 == "5"; //true PHP是弱类型语言(js中的变量类似) echo 5 === "5"; //false 完全等于
(6) Logical operations
AND(logical AND) OR(logical OR) XOR(logical exclusive OR) &&(logical AND) ||(logical OR) !(logical NOT)
var_dump(5 && ""); //false var_dump(5 && "2"); //true var_dump(5 || ""); //true var_dump(0 xor 1); //true var_dump(0 xor 0); //false var_dump(1 xor 1); //false
1. PHP operators
There is a rich set of operators in PHP, most of which come directly from the C language. According to different functions, operators can be divided into: arithmetic operators, string operators, assignment operators, bit operators, conditional operators, and logical operators. When various operators are in the same expression, their operations have a certain priority.
(1) Arithmetic operations
+ - * / % ++ --
(2) String operator
There is only one string operator. (dot) is the English period. It can concatenate strings to form a new string, or it can concatenate strings with numbers, and the types will be automatically converted.
$a="dawanganban"; $b="123"; echo $a.$b; //输出结果:dawanganban123(3) Assignment operator
= += -= *= /= %= .= $a="dawanganban"; $a.=1; $a.=2; $a.=3; echo $a.$b; //输出结果:dawanganban123(4) Bit operators& | ~ ^ >
(5) Comparison operator
> = === !==: is not equal to sum! =Same
===: Identity, the values are equal and the types are consistent
! ==: non-identity, values are not equal or types are inconsistent
echo 5 == "5"; //true PHP是弱类型语言(js中的变量类似) echo 5 === "5"; //false 完全等于
- AND(logical AND) OR(logical OR) XOR(logical exclusive OR) &&(logical AND) ||(logical OR) !(logical NOT)
(6) Logical operations
var_dump(5 && ""); //false var_dump(5 && "2"); //true var_dump(5 || ""); //true var_dump(0 xor 1); //true var_dump(0 xor 0); //false var_dump(1 xor 1); //false
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