相加運算子（+）
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
相加運算子（+）用來處理數字的相加或是進行字串的串聯。
嘗試一下
語法
js
x + y
範例
數字相加
js
// Number + Number -> addition
1 + 2; // 3
// Boolean + Number -> addition
true + 1; // 2
// Boolean + Boolean -> addition
false + false; // 0
字串串聯
js
// String + String -> concatenation
"foo" + "bar"; // "foobar"
// Number + String -> concatenation
5 + "foo"; // "5foo"
// String + Boolean -> concatenation
"foo" + false; // "foofalse"
規範
| Specification |
|---|
| ECMAScript Language Specification # sec-addition-operator-plus |
瀏覽器相容性
BCD tables only load in the browser