技術標籤：Angular

• ngFor迴圈物件取值

data = {};
<div *ngFor="let item of data | keyvalue"></div>    

• reduce 計算重複累計值

  // Get the total duration
  getCountNumber(dataArr): any{
    return dataArr.reduce((prev, next) => {
      prev[next.eventType] = {
        count: (prev[next.eventType]?.count + 1) || 1,
        status: true,
        show: true
      };
      return prev;
    }, {});
  }
 

• 深拷貝

  // Deep copy
  deepCopy(oldObj: any): any {
    let newObj = oldObj;
    if (oldObj && typeof oldObj === 'object') {
      if (oldObj instanceof Date) {
        return new Date(oldObj.getTime());
      }
      newObj = Object.prototype.toString.call(oldObj) === '[object Array]' ? [] : {};
      for (const i in oldObj) {
        if (oldObj.hasOwnProperty(i)) {
          newObj[i] = this.deepCopy(oldObj[i]);
        }
      }
    }
    return newObj;
  }