angularjs directive 中 scope '=?' 表达的是什么意思？
Copyright 2014-2025 https://www.php.cn/ All Rights Reserved | php.cn | 湘ICP备2023035733号
2
774
![ThinkPHP5快速开发企业站点[全程实录]](https://img.php.cn/upload/course/000/000/068/6253d918a3ce7278.png)
收藏
If the parent scope property doesn't exist, it will throw a NON_ASSIGNABLE_MODEL_EXPRESSION exception. You can avoid this behavior using
=?or=?attrin order to flag the property as optional.If you want to shallow watch for changes (i.e. $watchCollection instead of $watch) you can use
=*or=*attr(=*?or=*?attrif the property is optional).双向的数据绑定，你可以看看这里传送门