请问这种写法 如何更加完美 更加精简

Question

let _suffix = res.fileExt || res.fileExt.substring(1);      console.log(res.fileExt.substring(1))      if (_suffix == 'jpeg' || _suffix == 'jpg' || _suffix == 'png' || _suffix == 'bmp'|| _suffix == 'gif' ) {        alert(1);         this.fileDetail.iFileType = 'img'      }else if(_suffix == 'mov' || _suffix == 'avi' || _suffix == 'rm' || _suffix == 'rmvb' || _suffix == 'mpeg' || _suffix == 'mpg'){          this.fileDetail.iFileType = 'video'      }else{        this.fileDetail.iFileType = 'none'      }

Answer 1

『 Javascript 策略模式 』

const _suffix = res.fileExt || res.fileExt.substring(1)

const img = 'img'

const video = 'video'

const mapping = {

    jpeg: img,

    jpg: img,

    png: img,

    bmp: img,

    gif: img,

    mov: video,

    avi: video,

    rm: video,

    rmvb: video,

    mpeg: video,

    mpg: video,

}

this.fileDetail.iFileType = mapping[_suffix] || 'none'