初学小程序，测试switch。新建项目，然后修改app.json，添加： "useExtendedLib": { "weui": true }, "usingComponents": { "mp-cells": "weui-miniprogram/cells/cells", "mp-cell": "weui-miniprogram/cell/cell", "mp-form": "weui-miniprogram/form/form" } 修改index.wxml： <!--index.wxml--> <mp-cell title="测试" ext-class=""> <switch slot="footer" bindchange="bindSwitchChange" /> </mp-cell> 修改index.js： // index.js Page({ data: { shouldTest: true }, bindSwitchChange(e) { this.setData({ shouldTest: e.detail.value }); console.log(shouldTest); } }) 然后报错： ReferenceError: shouldTest is not defined     at zo.bindSwitchChange (index.js? [sm]:9)     at Object.i.safeCallback (WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1)     at WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1     at Cn (WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1)     at WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1     at oe (WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1)     at ie (WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1)     at WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1     at WAServiceMainContext.js?t=wechat&s=1667317212484&v=2.27.0:1     at o.emit (WAServiceMainContext.js?t=wechat&s=1667317212484&v=2.27.0:1)(env: macOS,mp,1.06.2209190; lib: 2.27.0) errorReport @ WAServiceMainContext.js?t=wechat&s=1667317212484&v=2.27.0:1 thirdErrorReport @ WAServiceMainContext.js?t=wechat&s=1667317212484&v=2.27.0:1 (anonymous) @ WAServiceMainContext.js?t=wechat&s=1667317212484&v=2.27.0:1 (anonymous) @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 i.safeCallback @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 i.call @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 message @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 i.safeCallback @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 (anonymous) @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 Cn @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 (anonymous) @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 oe @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 ie @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 (anonymous) @ WASubContext.js?t=wechat&s=1667317212484&v=2.27.0:1 (anonymous) @ WAServiceMainContext.js?t=wechat&s=1667317212484&v=2.27.0:1 emit @ WAServiceMainContext.js?t=wechat&s=1667317212484&v=2.27.0:1 dispatch @ WAServiceMainContext.js?t=wechat&s=1667317212484&v=2.27.0:1 cb @ WAServiceMainContext.js?t=wechat&s=1667317212484&v=2.27.0:1 a @ VM146 asdebug.js:10 c @ VM146 asdebug.js:10 (anonymous) @ VM146 asdebug.js:1 f @ VM146 asdebug.js:1 g @ VM146 asdebug.js:1 (anonymous) @ VM146 asdebug.js:1 _ws.onmessage @ VM146 asdebug.js:1 请问我的问题出在哪里呢？谢谢！