javascript - 无法访问在nodejs中更改其内部值的变量

Question

let lines = ["Hi","Bye","Gone"];

let match = false;

for(line in lines){
  if(line === "Bye"){
  match = true;
  }
}

console.log(match);

我想在 for 函数之外使用“匹配”变量的更改值。我怎样才能做到这一点？

Answer 1

您需要使用 for ... of statement而不是 for ... in statement获取数组的元素而不是索引。

请看，why not use for ... in for iterating arrays .

不要忘记声明变量 line。

let lines = ["Hi","Bye","Gone"];
let match = false;

for (let line of lines) {
    if (line === "Bye") {
        match = true;
    }
}

console.log(match);