如何删除 TypeScript 中的隐式声明答案

【问题标题】：How to remove implicit declaration in TypeScript如何删除 TypeScript 中的隐式声明
【发布时间】：2021-07-09 19:36:33
【问题描述】：

我想删除我的隐式声明错误：

元素隐式具有“任意”类型，因为“字符串”类型的表达式不能用于索引类型“{ 1: { length: number; }; 2：{长度：数字； }; 3：{长度：数字； }; 4：{长度：数字； }; }'

我是否为特定功能声明和接口？每当访问 steps 常量的索引时，都会发生此错误。

interface Step {
  length: number
}

interface Steps {
  [index: number]: Step
}

const min_x = 0
const max_x = 1
const steps = {
  1: { length: 1 },
  2: { length: 1 },
  3: { length: 1 },
  4: { length: 1 }
}
const sum = Object.keys( steps ).reduce( ( sum, key ): number => sum + parseFloat( steps[key].length || 0 ), 0 )
let start = min_x
Object.keys( steps ).forEach( ( key: any ) => {
  steps[ key ][`start`] = start;
  steps[ key ][`stop`] = start + ( steps[ key ].length / sum );
  start = start + ( steps[ key ].length / sum );
} )

【问题讨论】：

标签： typescript

【解决方案1】：

这对你在 ts 操场上工作正常吗？

界面步骤{ 长度：数字开始？：号码停止？：数字 }

interface Steps {
    [index: number]: Step
}

const min_x = 0
const max_x = 1
const steps: Steps = {
    1: { length: 1 }
}

const sum = Object.keys(steps).reduce((sum, key): number => sum + steps[+key].length, 0)
let start = min_x
Object.keys(steps).forEach((key: any) => {
    steps[key][`start`] = start;
    steps[key][`stop`] = start + (steps[key].length / sum);
    start = start + (steps[key].length / sum);
})

【讨论】：

【解决方案2】：

试试下面的sn-p，可以参考我改过的代码。

interface Step {
  length: number,
  start?: number,
  stop?: number
}

interface Steps {
  [index: string]: Step // index type is string or number, string would be better.
}

const min_x = 0
const max_x = 1
const steps: Steps = {
  1: { length: 1 },
  2: { length: 1 },
  3: { length: 1 },
  4: { length: 1 }
}

// parseFloat only accepts type of string
const sum = Object.keys( steps ).reduce( ( sum, key ): number => sum + parseFloat( String(steps[key].length || 0) ), 0 )
let start = min_x
Object.keys( steps ).forEach( ( key ) => {
  steps[ key ][`start`] = start;
  steps[ key ][`stop`] = start + ( steps[ key ].length / sum );
  start = start + ( steps[ key ].length / sum );
} )

【讨论】：