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Home Backend Development PHP Tutorial What are the commonly used expressions in php?

What are the commonly used expressions in php?

Apr 29, 2024 pm 12:33 PM

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

What are the commonly used expressions in php?

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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