相关疑难解决方法(0)

我在Angular 2应用程序中收到此编译错误:

TS7015: Element implicitly has an 'any' type because index expression is not of type 'number'.

导致它的代码是:

getApplicationCount(state:string) {
    return this.applicationsByState[state] ? this.applicationsByState[state].length : 0;
  }

但是,这不会导致此错误:

getApplicationCount(state:string) {
    return this.applicationsByState[<any>state] ? this.applicationsByState[<any>state].length : 0;
  }

这对我没有任何意义.我想在第一次定义属性时解决它.目前我正在写:

private applicationsByState: Array<any> = [];

但有人提到问题是试图在数组中使用字符串类型作为索引,我应该使用映射.但我不知道该怎么做.

有你的帮助!

Trying out TypeScript for a React project and I'm stuck on this error:

Element implicitly has an 'any' type because expression of type 'string' can't be used to index type '{ train_1: boolean; train_2: boolean; train_3: boolean; train_4: boolean; }'.
  No index signature with a parameter of type 'string' was found on type '{ train_1: boolean; train_2: boolean; train_3: boolean; train_4: boolean; }'

Which appears when I try to filter the array in my component

.filter(({ name }) => plotOptions[name]); …

假设我有这个：

const color = {
    red: null,
    green: null,
    blue: null
};

const newColor = ['red', 'green', 'blue'].filter(e => color[e]);

错误在color[e]底部附近：

元素隐式地具有“ any”类型，因为类型“ string”的表达式不能用于索引类型“ {red：null; 绿色：null；蓝色：null；}'。在类型“ {{red：null;}”上找不到带有参数“ string”的索引签名。绿色：null；蓝色：null；}'。

我尝试在TypeScript文档上到处查找，但是我interface对此到底想怎么想，以便它可以接受color[e]？