微信小程序读取nfc门卡信息

首先通过wx.getNFCAdapter()来获取nfc实例

然后调用startDiscovery获取当前手机nfc状态

已经打开了nfc的就可以调用监听方法onDiscovered

监听到数据后setData把数据展示出来就ok了，方法如下

    nfc() {
        const nfc = wx.getNFCAdapter()
        this.nfc = nfc
        let _this = this

        function discoverHandler(res) {
            const data = new Uint8Array(res.id)
            let str = ""
            data.forEach(e => {
                let item = e.toString(16)
                if (item.length == 1) {
                    item = '0' + item
                }
                item = item.toUpperCase()
                str += item
            })
            _this.setData({
                newCardCode: str
            })
            wx.showToast({
                title: '读取成功！',
                icon: 'none'
            })
        }
        nfc.startDiscovery({
            success(res) {
                wx.showToast({
                    title: 'NFC读取功能已开启！',
                    icon: 'none'
                })
                nfc.onDiscovered(discoverHandler)
            },
            fail(err) {if(!err.errCode){
                  wx.showToast({
                    title: '请检查NFC功能是否正常!',
                    icon: 'none'
                  })
                  return
                }
                switch (err.errCode) {
                    case 13000:
                      wx.showToast({
                        title: '设备不支持NFC!',
                        icon: 'none'
                      })
                      break;
                    case 13001:
                      wx.showToast({
                        title: '系统NFC开关未打开!',
                        icon: 'none'
                      })
                      break;
                    case 13019:
                      wx.showToast({
                        title: '用户未授权!',
                        icon: 'none'
                      })
                      break;
                    case 13010:
                      wx.showToast({
                        title: '未知错误!',
                        icon: 'none'
                      })
                      break;
                  }
            }
        })
    },

 

 

     nfcRead ()  {

         console . log( ' nfc ')

         const  nfc  =  wx . getNFCAdapter()

         this . nfc  =  nfc

         let  _this  =  this

         function  discoverHandler ( res )  {

             console . log( ' discoverHandler ' ,  res)

             const  data  =  new  Uint8Array( res . id)

             let  str  =  ""

             data . forEach( e  =>  {

                 let  item  =  e . toString( 16)

                 if ( item .length  ==  1)  {

                     item  =  ' 0 '  +  item

                 }

                 item  =  item . toUpperCase()

                 console . log( item)

                 str  +=  item

             })

             _this . setData( {

                newCardCode :  str

             })

             console . log( str)

             wx . showToast( {

                title :  ' 读取成功！ ' ,

                icon :  ' none '

             })

         }

         nfc . startDiscovery( {

             success ( res )  {

                 console . log( res)

                 wx . showToast( {

                    title :  ' NFC读取功能已开启！ ' ,

                    icon :  ' none '

                 })

                 nfc . onDiscovered( discoverHandler)

             },

             fail ( err )  {

                 console . log( ' failed to discover: ' ,  err)

                 if( ! err . errCode) {

                   wx . showToast( {

                    title :  ' 请检查NFC功能是否正常! ' ,

                    icon :  ' none '

                   })

                   return

                 }

                 switch ( err . errCode)  {

                     case  13000 :

                       wx . showToast( {

                        title :  ' 设备不支持NFC! ' ,

                        icon :  ' none '

                       })

                       break;

                     case  13001 :

                       wx . showToast( {

                        title :  ' 系统NFC开关未打开! ' ,

                        icon :  ' none '

                       })

                       break;

                     case  13019 :

                       wx . showToast( {

                        title :  ' 用户未授权! ' ,

                        icon :  ' none '

                       })

                       break;

                     case  13010 :

                       wx . showToast( {

                        title :  ' 未知错误! ' ,

                        icon :  ' none '

                       })

                       break;

                   }

             }

         })

     },