小编Sgt*_*nut的帖子

这是我的验证架构：

const validationSchema = Yup.object().shape({
      person: Yup.object().shape({
        name: Yup.string().required('Field is required'),
        surname: Yup.string().required('Field is required'),
        middleName: Yup.string().required('Field is required'),
        email: Yup.string()
          .email('Wrong e-mail format')
          .required('Field is required')
      }),
      company: Yup.object().shape({
        name: Yup.string().required('Field is required'),
        address: Yup.string().required('Field is required'),
        email: Yup.string()
          .email('Wrong e-mail format')
          .required('Field is required')
      })
    });

而且 React State 中有两个变量：isPerson和isCompany。如何使验证工作条件，例如，如果isPerson是真的，那么person在validationSchema需要进行验证？

我在 React Native 项目中使用 Eslint，在这段代码中：

export default class AuthLoadingScreen extends React.Component {
  constructor() {
    super();
    this.bootstrapAsync();
  }

  bootstrapAsync = async () => {
    const userToken = await AsyncStorage.getItem('userToken');
    this.props.navigation.navigate(userToken ? 'App' : 'Auth');
  };

  render() {
    return (
      <View style={styles.container}>
        <ActivityIndicator />
        <StatusBar barStyle="default" />
      </View>
    );
  }
}

Eslint 给出警告：“必须使用解构道具赋值”。我试图将分配更改为

const navigation = this.props;
navigation.navigate(userToken ? 'App' : 'Auth');

但它给出了一个错误：“未定义不是一个对象”

编辑： 将构造函数更改为：

constructor(props) {
    super(props);
    this.bootstrapAsync(props);
  }

现在代码运行没有错误

有两个数组：

[
  {"id": "5c5030b9a1ccb11fe8c321f4", "quantity": 1},
  {"id": "344430b94t4t34rwefewfdff", "quantity": 5},
  {"id": "342343343t4t34rwefewfd53", "quantity": 3}
]

和

[
  {"id": "5c5030b9a1ccb11fe8c321f4", "quantity": 2},
  {"id": "344430b94t4t34rwefewfdff", "quantity": 1}
]

如何将它们合并为一个求和量？

[
  {"id": "5c5030b9a1ccb11fe8c321f4", "quantity": 3},
  {"id": "344430b94t4t34rwefewfdff", "quantity": 6},
  {"id": "342343343t4t34rwefewfd53", "quantity": 3}
]

其中之一有时可能是空的

我想在 iOS 上的 Xamarin 中隐藏后退按钮的文本，我试过：

<Style TargetType="NavigationPage">
<Setter Property="BackButtonTitle" Value="" />
</Style>

和这个代码：

<Style TargetType="ContentPage">
<Setter Property="NavigationPage.BackButtonTitle" Value="" />
</Style>

但文字仍然出现

解决了：

iOS渲染器：

[assembly: ExportRenderer(typeof(ContentPage), typeof(BackButtonPag))]
[assembly: ExportRenderer(typeof(NavigationPage), typeof(BackButtonNav))]

public class BackButtonPag : PageRenderer
    {
        public override void ViewWillAppear(bool animated)
        {
            base.ViewWillAppear(animated);

            if (NavigationController != null)
                NavigationController.TopViewController.NavigationItem.BackBarButtonItem = new UIBarButtonItem("", UIBarButtonItemStyle.Plain, null);
        }
    }

    public class BackButtonNav : NavigationRenderer
    {
        public override void ViewWillAppear(bool animated)
        {
            base.ViewWillAppear(animated);

            NavigationBar.TopItem.BackBarButtonItem = new UIBarButtonItem("", UIBarButtonItemStyle.Plain, null);
        }
    }

也添加这个

NavigationPage.BackButtonTitle = ""

到 …

我的目标是在我的 React Native 应用程序中制作一个带有 3D 模型的页面，我发现最简单的方法是使用expo-threelibrary。但它需要Expo，所以在我的情况下这不是一个选择。我还能用什么来做到这一点？任何帮助表示赞赏。

数组看起来像

products = [
    {
      "id": "5c94aa7b7a37631ce2a97a72",
      "material": "5c9485d37804946bc487ce59",
    },
    {
      "id": "5c94aa7b7a37631ce2a97a72",
      "material": "5c94862a7804946bc487ce5e",
    },
    {
      "id": "5c94aa7b7a37631ce2a97a72",
      "material": "5c9486397804946bc487ce61",
    },
    {
      "id": "5c94a0a87a37631ce2a979de",
      "material": "5c9485d37804946bc487ce59",
    },
    {
      "id": "5c94a0a87a37631ce2a979de",
      "material": "5c94862a7804946bc487ce5e",
    },
    {
      "id": "5c94a0a87a37631ce2a979de",
      "material": "5c9486397804946bc487ce61",
    }
  ]

当我尝试使用id="5c94aa7b7a37631ce2a97a72"和仅删除一项material="5c9485d37804946bc487ce59"

我使用过滤功能

filtered = products.filter(x => x.id !== id && x.material !== material);

它将删除所有具有这些ID和材料的产品。在此功能中设置条件的正确方法是什么？