javascript - 如果定义了所有属性，则将变量设置为 true

Question

如果定义了渲染组件的所有必需属性，将变量设置为 true 的最简单方法是什么？

例如:

  renderThing() {
    const {
      bookState,
      totalPrice,
      agentWebPriceDelta,
      numberOfChargeablePassengers,
    } = this.props;

      const requiredProps = bookState !== 'undefined' && totalPrice !== 'undefined' && agentWebPriceDelta !== 'undefined' && numberOfChargeablePassengers !== 'undefined';

      return requiredProps && (
          <ComponentToBeRendered
            ...
          />
        );
    }
  }

这是为了阻止出现如下错误:

Required prop totalPrice was not specified in ComponentToBeRendered.'

Answer 1

注意:删除 undefined 两边的引号:

const requiredProps = bookState !== undefined && totalPrice !== undefined && agentWebPriceDelta !== undefined && numberOfChargeablePassengers !== undefined;

您还可以使用Array.prototype.reduce 像这样(不确定是否更具可读性):

const requiredProps = [
  bookState,
  totalPrice,
  agentWebPriceDelta,
  numberOfChargeablePassengers
].reduce((prev, value) => prev && value !== undefined, true);