Question

我有类似accessing react props in selectors文档中的用例，但在我的情况下，假设visibilityFilter来自道具。有没有办法如何实现如下所示？

export const getVisibleTodos = createSelector(
  getTodos,
  (todos, props) => {
    // props is undefined 
    switch (props.visibilityFilter) {
      case 'SHOW_ALL':
        return todos
      case 'SHOW_COMPLETED':
        return todos.filter(t => t.completed)
      case 'SHOW_ACTIVE':
        return todos.filter(t => !t.completed)
    }
  }
)

我仍然需要对它进行适当的记忆，但我想这是第二步。

Answer 1

Props (or ownProps) is the second argument passed to any mapStateToProps function.

使用它，您可以将所需的属性提取为resultFunc的输入之一。

export const getVisibleTodos = createSelector(
  getTodos,
  (state, props) => props.visibilityFilter,
  (todos, visibilityFilter) => {
    switch (visibilityFilter) {
      case 'SHOW_ALL':
        return todos
      case 'SHOW_COMPLETED':
        return todos.filter(t => t.completed)
      case 'SHOW_ACTIVE':
        return todos.filter(t => !t.completed)
    }
  }
)

从选择器的resultFunc访问道具

1 个答案: