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我正在尝试使用 mapStateToProps 将对象（称为讲座）从状态传递给道具。该对象存在于对象数组中。我相信我犯了一个语法错误，但不确定正确的语法应该是什么，因为下面的代码适用于循环遍历父对象（包含其中的对象）并在父对象中选择正确的对象。

//This code works to cycle through a parent Object that contains objects inside of it; returning the object inside that has the correct ID.
//It doesn't work in this situation ... where instead of having objects inside a parent object, 
//there are obejcts inside a parent Array.

const mapStateToProps = (state) => {

    const lectureID = state.selectedLectureID;
    console.log(lectureID);          <--- THIS SHOWS THE CORRECT ID OF THE OBJECT I AM TRYING TO READ.

    const lectures = state.firestore.ordered.lectures;
    console.log(lectures);        <------ THIS SHOWS THE ARRAY OF OBJECTS, INCLUDING ONE OBJECT THAT HAS THE LECTURE ID FOUND ABOVE


    const selectedLecture= lectures ? lectures[lectureID] : null; <--- ERROR HERE... TRYING TO CYCLE THROUGH THE ARRAY OF LECTURES AND PASS THE LECTURE THAT HAS THE CORRECT LECTURE ID. IF NONE HAVE THIS ID, THEN IT SHOULD RETURN "null".
    console.log(selectedLecture);   <--- THIS RETURNS "undefined", SUGGESTING THE CODE ABOVE DIDN'T READ THROUGH THE ARRAY OF OBJECTS AND SELECT THE ONE WITH THE CORRECT ID.
    

return {

        selectedLecture: selectedLecture,
        
    }
}

注意：上面的代码将 LectureID 解释为数组中的索引，而不是试图识别对象数组中的对象 ID。我该如何纠正？

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1 回答 1

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我找到了一个替代解决方案：

与其尝试遍历 mapStateToProps 中的对象数组，我发现通过 Actions + Reducers 将具有特定 ID 的对象作为对象简单地传递并通过状态与内容交互更容易。

于 2020-07-24T22:47:44.453 回答