uni-app 常用写法

<button type="primary" @tap="btn">登录</button>

//判断信息是否填写
btn() {
  if (this.username.length <= 0) {
    uni.showToast({
      icon: 'none',
      title: '请输入用户名'
    });
    return;
  }
  if (this.pwd.length <= 0) {
    uni.showToast({
      icon: 'none',
      title: '请输入密码'
    });
    return;
  }
}

//登陆
uni.request({
  url: 'http://199.168.100.55:54723/ZycfService/login/login', //仅为示例，并非真实接口地址。
  data: {
    username: this.username,
    pass: this.pwd
  },success: (res) => {
    let list=JSON.stringify(res.data);
    console.log("返回数据状态:" + list);
    if(list=="[]"){
      uni.showToast({
        icon: 'none',
        title: '用户名或密码错误'
      });
      return;
    }
    uni.showToast({
      icon: 'none',
      title: '登录成功'
    });    
  },fail: () => {
    uni.showToast({
      icon: 'none',
      title: '网络异常,请稍后重试'
    });
  }

})



//加入缓存
uni.setStorage({
  key:'userinfo',
  data:{
    bh:_this.lists[0]['bh'],
    rolename:_this.lists[0]['rolename'],
    username:_this.lists[0]['username']

  }
})



//跳转
uni.navigateTo({
  url: '../home/home',
});




onLoad() {
  //首先将实例指针保存到全局变量 _this 方便在异步请求中访问实例本身
  _this = this;
  uni.getStorage({
    key: 'userinfo',
    success: function(res) {
      const listdata = res.data;
      _this.list = listdata;
      console.log("数据是:" + _this.list.username)
    }
}



---------------

uni.chooseImage({
    count: 6, //可以选择图片的张数
    sizeType: ['original', 'compressed'], //可以指定是原图还是压缩图，默认二者都有
    sourceType: ['album'], //从相册选择  默认是两个都有
    success: function (res) {
        console.log(JSON.stringify(res.tempFilePaths));
    //返回结果
    }
});
uni.previewImage(OBJECT)


uni.chooseImage({
  count: 6,
  sizeType: ['original', 'compressed'],
  success: function(res) {
    // 预览图片
    //  uni.previewImage({
    //    urls: res.tempFilePaths
    //  });

    for(var i=0;i< res.tempFilePaths.length;i++){
        console.log("第"+i+"张图片路径:"+res.tempFilePaths[i]);
      }

    uni.getImageInfo({
      src:res.tempFilePaths[0],     
      success:function(image){
        console.log("图片路径:"+image.path);
      }
    });
  }
});
}