Check box error

About elementUI checkBox Report errors Cannot read property ‘length‘ of undefined - Simple books Use element-ui Of checkbox Plugin error reporting vue.runtime.esm.js?2b0e:1888 TypeError: Cannot read property ‘length‘ of un_ Blue deciduous blog -CSDN Blog

Use elementUI Medium el-checkbox run into sb. Cannot read property ‘length‘ of undefined What should we do about mistakes ？_lt Blog to work hard -CSDN Blog

When modifying

 

When adding  

solve ：

vue Front-end direction list Add elements and assign values to objects in _ Rampant Shanjiao's blog -CSDN Blog _vue Go to list Add object in

 

this.questionList = this.questionForm.questionList;
this.questionList.forEach(element => {
    element['value']=[]
});