Commonly used expressions in PHP include: arithmetic expressions: used for mathematical operations comparison expressions: comparing two values ??logical expressions: combinational logic conditional expressions: simplified if-else statements array expressions : Create array string expression: Create string
Commonly used expressions in PHP
Provided in PHP A variety of expressions for performing logical calculations in code. The following are some of the most commonly used expressions in PHP:
1. Arithmetic expressions
Arithmetic expressions are used to perform mathematical operations. The following operators can be used:
- Addition ( )
- Subtraction (-)
- Multiplication (*)
- Division (/)
- Modulo operation (%)
For example:
$result = 10 + 5 * 2; // 20
2. Comparison expression
Comparison expressions are used to compare two values. The following operators can be used:
- Equal (==)
- Not equal (!=)
- Greater than (>)
- Less than (<)
- Greater than or equal to (>=)
- Less than or equal to (<=)
For example:
if ($x == 10) { // 執(zhí)行操作 }
3. Logical expressions
Logical expressions are used to combine logical conditions. The following operators can be used:
- AND (&&)
- OR (||)
- NOT (!)
For example:
if ($x > 10 && $y < 5) { // 執(zhí)行操作 }
4. Conditional expression (ternary operator)
Conditional expression is a simplified if-else statement. It has the following syntax:
(condition) ? true_value : false_value
For example:
$result = ($x > 0) ? "positive" : "negative";
5. Array expression
Array expression is used to create array. The syntax is as follows:
[key1 => value1, key2 => value2, ...]
For example:
$arr = ['name' => 'John', 'age' => 25];
6. String expression
String expression is used to create string. The syntax is as follows:
"string"
or
'string'
For example:
$name = "John Smith";
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