在 Array Angular 和 Typescript 中查找最小和最大元素
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Find smallest & largest element in Array Angular & Typescript
提问by Jignesh Mistry
Hello All I have array & i need to perform various operation like sum, total, average. All these 3 are achieved, Now I need to find the minimum & maximum value in array. I am stucked on this below is the code.
大家好，我有数组，我需要执行各种操作，例如总和、总计、平均值。所有这三个都实现了，现在我需要找到数组中的最小值和最大值。我被困在下面是代码。
Below is TS Part
以下是 TS 部分
people: Array<number> = [1, 2, 3, 4, 5];
total: number = 0;
arrayLength: number = this.people.length;
average: number = 0;
sum() {
for (var i in this.people) { this.total += this.people[i]; }
}
ngOnInit() {
this.sum();
this.average = (this.total / this.arrayLength);
}
Below is HTML Part
下面是 HTML 部分
<span *ngFor="let p of people" style="font-size:18px">{{p}} </span><br><br>
<button >Quantity</button> = {{arrayLength}}<Br><br>
<button >Average</button> = {{average}}<Br><br>
<button >Sum</button> <span *ngIf="sumShow"> = {{total}}</span><Br><br>
回答by Tomasz Kula
Use Math.maxand Math.mincombined with the spread operator.
使用Math.max并Math.min与扩展运算符结合使用。
get max() {
return Math.max(...this.people);
}
get min() {
return Math.min(...this.people);
}
回答by Krishna Rathore
use reducefor this.
reduce为此使用。
Demo on Stackblitz
sum() {
this.total = this.people.reduce((a, b)=>a + b);
}
ngOnInit() {
this.sum();
this.max = this.people.reduce((a, b)=>Math.max(a, b));
this.min = this.people.reduce((a, b)=>Math.min(a, b));
this.average = (this.total / this.arrayLength);
}
<span *ngFor="let p of people" style="font-size:18px">{{p}} </span><br><br>
<button >Quantity</button> = {{arrayLength}}<Br><br>
<button >Average</button> = {{average}}<Br><br>
<button >Sum</button> <span > = {{total}}</span><Br><br>
<button >Max</button> <span > = {{max}}</span><Br><br>
<button >Min</button> <span > = {{min}}</span><Br><br>
回答by baao
You could create yourself a little helper class that does those operations for you and is reusable throughout your code
您可以为自己创建一个小助手类，为您执行这些操作，并且可以在整个代码中重用
export class MathOps {
array: number[];
constructor(array: number[]) {
this.array = array;
}
sum(): number {
return this.array.reduce((a, b) => a + b, 0);
}
avg(): number {
return this.sum() / this.array.length;
}
max(): number {
return Math.max(...this.array);
}
min(): number {
return Math.min(...this.array);
}
}
const ops = new MathOps([1, 2, 3, 4, 5]);
console.log(ops.avg());
console.log(ops.max());
console.log(ops.min());
console.log(ops.sum());
Note:
笔记：
Depending on use case, you'll want to extend this to cache results...
根据用例，您需要将其扩展到缓存结果...
回答by Anuradha Gunasekara
You can use Array.reduceand Math.max(), Math.min()for this.
为此，您可以使用Array.reduce和。Math.max()Math.min()
const people = [1,2,3,4,5];
const max = people.reduce((a, b) => Math.max(a, b)); // 5
const min = people.reduce((a, b) => Math.min(a, b)); // 1
const sum = people.reduce((a, b) => a+b, 0); // 15
And you can find a working example in here
你可以在这里找到一个工作示例
