1. `${}` vue.js中的实现变量和字符串的拼接 用法: return `${left}${right}`; 2. String() 用法:return String(left)+String(right); return left+String(right); 3. toString() return left.toString()+right.toString(); 4. 字符串拼接 return left+''+right; 参考:数据类型转换_牛客题霸_牛客网 (nowcoder.com)