vue elementui rules根据条件判断下一个选项必填和非必填的校验

<el-form-item label="HyperLink" prop="target" :rules="formInfo.type === 1?formRule.target:[{ required: false}]">
      <el-input   v-model="formInfo.target" clearable size="small" placeholder="Please select related content" @focus="selectArticle"></el-input>
</el-form-item>

formRule: {
       title: [
            { required: true, message: 'Please enter Banner title', trigger: 'blur' },
            { min: 1, max: 50, message: '1 to 50 characters', trigger: 'blur' }
       ],
        img: [
           { required: true, message: 'Please select a cover image', trigger: 'change' }
        ],
        type: [
           { required: true, message: 'Please select a jump type', trigger: 'change' }
       ],
       target:[
           { required: true, message: 'Please write a content', trigger: 'blur' }
      ] 
},