在JavaScript中，数组和集合是不同的，尽管它们有点相似，但在这里react需要一个数组。 您需要从集合中创建一个数组并应用它。

let homeArray = new Array(homes.length);
let i = 0

for (var key in homes) {
    homeArray[i] =  homes[key];
    i = i + 1;
}

使用时刻格式，因为那是日期…转换为日期格式… 时刻(array_list_item.close_date) .format(“;”)}

注意:React不会在map函数中显示这种类型的日期格式

“created_at”:“2018 - 09 - 18 t16:39:22.184z”,

只是添加到其他选项，我试图通过点方法访问主对象内的嵌套对象，如: this.state.arrayData.CompleteAdress.Location 在这种情况下，位置是完整地址内嵌套的对象，这就是为什么我不能简单地用点符号访问它。

因此，如果您面临同样的问题，请尝试JSON。解析，以便访问嵌套对象，然后进行相应操作。

我也有同样的问题。在我的情况下，我没有呈现项目的价值。我最初的代码是，

        keyExtractor={(item, index) => item.id}
        data={courseGoals} 
        renderItem={itemData => (
          <View style={styles.listitem}> 
              <Text>{itemData.item}</Text> 
          </View>
        )} 
      />

我只是简单地加了一句。价值’，而且它起作用了!

        keyExtractor={(item, index) => item.id}
        data={courseGoals} 
        renderItem={itemData => (
          <View style={styles.listitem}> 
              <Text>{itemData.item.value}</Text> 
          </View>
        )} 
      />

您的数据家是一个数组，因此您必须使用array .prototype.map()迭代数组才能使其工作。

return (
    <div className="col">
      <h1>Mi Casa</h1>
      <p>This is my house y&apos;all!</p>
      {homes.map(home => <div>{home.name}</div>)}
    </div>
  );

我今天得到了同样的错误，但与这个问题中发布的场景相比，情况有所不同。希望下面的解决方案能帮助到一些人。

下面的渲染函数足以理解我的场景和解决方案:

render() {
    let orderDetails = null;
    if(this.props.loading){
        orderDetails = <Spinner />;
    }
    if(this.props.orders.length == 0){
        orderDetails = null;
    }
    orderDetails = (
        <div>
            {
                this.props.orders && 
                this.props.orders.length > 0 && 
                this.props.orders.map(order => (
                <Order 
                    key={order.id}
                    ingredient={order.ingredients}
                    price={order.price} />
                ))
            }
        </div>
    );
    return orderDetails;
}

在上面的代码片段中:如果return orderDetails作为return {orderDetails}发送，那么尽管'orderDetails'的值(值为<Spinner/>或null或与<Order />组件相关的JSX)，这个问题中发布的错误仍然会弹出。

错误描述:React -dom.development.js:57未捕获的不变性违规:对象作为React子对象无效(发现:带有键{orderDetails}的对象)。如果要呈现子元素的集合，请使用数组。

我们不能从render()方法内部的返回调用中返回JavaScript对象。原因是React期望一些JSX, false, null, undefined, true在UI中呈现，而不是一些JavaScript对象，当我使用返回{orderDetails}时，我试图呈现，因此得到如上所述的错误。

有效:

<div />

<div></div>

<div>{false}</div>

<div>{null}</div>

<div>{undefined}</div>

<div>{true}</div>

无效:

<div>{orderDetails}</div> // This is WRONG, orderDetails is an object and NOT a valid return value that React expects.

Edit: I also got this error on my company's test server used by QA's for their testing. I pointed my local code to that test server and tested the scenario in which this error was reported by QA team and found NO ERROR in my local machine. I got surprised. I re-checked multiple number of times, re-checked the scenario with QA team and I was doing right but still I was not able to replicate the issue. I consulted my fellow devs but still were not able to figure out the root cause. So keeping with the information in the error message I started scanning all the code I had deployed in my last deployment commit ( to be more specific last 4-5 commits because I suspected it could be there from last few deployments but was caught in the current deployment), especially all the components I had developed and found that there was a component - inside which there was no specified condition being met so it was returning NOTHING from it. So see below sample pseudo code. I hope it helps.

render () {
return (
    {this.props.condition1 && (
       return some jsx 1
    )}

    {this.props.condition1 && (
       return some jsx 2
    )})
}

如果你在上面的伪代码中看到，如果条件1和条件2不满足，那么这个组件将从它呈现NOTHING，理想情况下，react组件必须从它返回一些JSX, false, null, undefined, true。