【Typechecking With PropTypes】

1、props类型检查

　　React has some built-in typechecking abilities. To run typechecking on the props for a component, you can assign the special propTypesproperty:

2、child个数设置

　　With React.PropTypes.element you can specify that only a single child can be passed to a component as children.

3、Default Prop Values

参考：https://facebook.github.io/react/docs/typechecking-with-proptypes.html

Typechecking With PropTypes