text: export function eventListener(instance, event, callback, once = false) {
    if (!instance || !event || !callback) {
      console.log('缺少参数错误')
      return
    }
    let isDone = false
    const handler = function() {
      if (isDone) {
        return
      }
      isDone = true
      callback && callback()
    }
    if (once) {
      instance.$once(event, handler)
    } else {
      instance.$on(event, handler)
    }
  }
  
  export function isUrl(str) {
    return /(?:jpeg|jpg|png|gif|webp)/i.test(str)
  }