Angular - 无法求和

Question

我想求和，但现在我尝试写函数和 console.log（总计）但它恰好是 'undefined'

app.ts

  saveTasks() {
    if (this.tasksToSave.length != 0) {
      for (let i = 0; this.tasksToSave.length > i; i++) {
        this.ticketService.setAddTasks(
          this.id,
          this.tasksToSave[i]
        )
      }
     }
   }
  sumPoint() {
    let total = 0
    if (this.tasksToSave.length != 0) {
      for (let i = 0; i < this.tasksToSave.length; i++) {
        total = total + this.tasksToSave[i].point
      }
    }
  }

app.html

total = {{total}}

Answer 1

将 total 变量放在 component 的 export 块中，如下所示：

    export class YourComponent implements OnInit {
      ...
      total: number = 0;
      ...    
      sumPoint() {        
          if (this.tasksToSave.length != 0) {
           for (let i = 0; i < this.tasksToSave.length; i++) {
            this.total = this.total + this.tasksToSave[i].point
           }
         }
       }          
      ...
    }

Angular - 无法求和

Angular - can't sum point

angular8