.join()的作用是连接一个字符串数组中的元素。
例如:
function buildName(firstName: string, ...restOfName: string[]) {
return firstName + " " + restOfName.join("-");
}
let employeeName = buildName("Joseph", "Samuel", "Lucas", "MacKinzie")
console.log(employeeName)
输出为
Joseph Samuel-Lucas-MacKinzie