Question

如果所有字段均有效，如何返回resolve（）否则返回拒绝？

let validateData = (data) => {
    let fields = [
        'Field1',
        'Field2',
        'Field3'
    ];

    return new Promise((resolve, reject) => {
        fields.forEach(field => {
            if (data.hasOwnProperty(field)) {
                // resolve if all matched
            } else {
                //reject?
            }
        });
    });
}

主要它将具有

try {
    await validateData(data);
} catch(err) {
    throw new Error(`${err}`);
}

Answer 1

如果数据对象上不存在任何字段，则在找到后立即拒绝。如果没有，您最终可以解决。

let validateData = (data) => {
    let fields = [
        'Field1',
        'Field2',
        'Field3'
    ];

    return new Promise((resolve, reject) => {
        fields.forEach(field => {
            if (!data.hasOwnProperty(field)) {
                reject();
            }
        });
        resolve();
    });
}

Answer 2

NavigationPageRenderer

如果其中任何一个属性无效，只需return new Promise((resolve, reject) => { fields.forEach(field => { if (!data.hasOwnProperty(field)) { reject(); return; } }); resolve(); });，否则，如果所有这些属性均有效，则不会将其放入if语句中，它将解决承诺。

Answer 3

错误对象将包含验证错误的描述：

let validateData = (data) => {
    let fields = [
        'Field1',
        'Field2',
        'Field3'
    ];
    return new Promise((resolve, reject) => {
        let errors = [];
        fields.forEach(field => {
            if (!data.hasOwnProperty(field)) {
                errors.push(`ValidationFieldError: ${field}`);
            }
        });

        errors.length ? reject(new Error(errors.join('\n'))) : resolve();
    });
}

Answer 4

如果所有验证有效的字段都需要异步操作，则可以使用Promise.all，只有在所有验证有效的字段都得到解决后，才能解决该问题。

例如

let validateData = async (data) => {
    let fields = [
        'Field1',
        'Field2',
        'Field3'
    ];

    let fieldsValidatedPromsises = [];


    fields.forEach(field => {
        let validationPromise = new Promise( function (resolve, reject) {
            if (data.hasOwnProperty(field)) {
                // resolve if all matched
            } else {
                //reject?
            }
        });

        fieldsValidatedPromsises.push(validationPromise);
    });

    return Promise.all(fieldsValidatedPromsises).then(function () {
        return true;
    })
    .catch(function () {
        return false;
    });
}

let c = await validateData(data);

if (c) {
    // All fields validation is successful
}
else {
    // One of field validation fails
}

Answer 5

一种优雅的方式是

let validateData = async (data) => {
    let fields = [
        'Field1',
        'Field2',
        'Field3'
    ];
    let promises = [];
    fields.forEach(field =>
        promises.push(new Promise((resolve) =>
            data.hasOwnProperty(field) ? resolve() : reject())
        )
    );
    return Promise.all(promises);
}

演示

let validateData = async(data) => {
  let fields = [
    'Field1',
    'Field2',
    'Field3'
  ];
  let promises = [];
  fields.forEach(field =>
    promises.push(new Promise((resolve) =>
      data.hasOwnProperty(field) ? resolve() : reject()))
  );
  return Promise.all(promises);
}

async function foo() {
  try {
    await validateData({
      'Field1': 1,
      'Field2': 2,
      'Field3': 3
    });
    console.log('valid here');
  } catch (err) {
    console.log('Invalid');
  }
}

foo();

Answer 6

还有另一种方法...

let validateData = (data) => {
    let fields = [
        'Field1',
        'Field2',
        'Field3'
    ];

    return new Promise((resolve, reject) => {
        fields.every(field => data.includes(field)) ? resolve() : reject();
    });
}

验证数据然后返回解析？

6 个答案: