角度6：错误TS2339：类型“ HTMLElement”上不存在属性“值”

Question

I have textarea which allow user to submit comments, I want to grab the date on time the comment is submitted, and save to json together with comment added :

after comment is submitted in json file I would like to have something like this:

 "comment": [
    {
      "id": 1,
      "username": "Michael Ross",
      "city": "New York USA",
      "date": "2018-01-01T00:00:00",
      "task_id": 1,
      "description": "Lorem ipsum dolor sit amet enim. Etiam ullamcorper. Suspendisse a pellentesque dui, non felis. Maecenas malesuada elit lectus felis, malesuada ultricies. Curabitur et lig"
    }
]

Problem: Right now when comment is submitted I have the following: no date is displayed:

 "comment": [
    {
      "id": 1,
      "username": "Michael Ross",
      "city": "New York USA",
      "task_id": 1,
      "description": "Lorem ipsum dolor sit amet enim. Etiam ullamcorper. Suspendisse a pellentesque dui, non felis. Maecenas malesuada elit lectus felis, malesuada ultricies. Curabitur et lig"
    }
]

Here is what I have tried so far to grab the date from entered comment.

HTML :

<form class="add-comments" [formGroup]="addForm" (keyup.enter)="addComments()">
      <input type="hidden" id="localTime" name="localTime">
    <div class="form-group">
      <textarea class="form-control" rows="1" placeholder="Add comments" formControlName="description" id="description"></textarea>
    </div>
  </form>

Here is method on compoents ts.

 addComments(task_id) {
    const formData = this.addForm.value;
    formData.task_id = task_id;
    this.userService.addComments(formData)
    .subscribe(data => {
      this.comments.push(this.addForm.value);
    });
    const date = new Date();
    const d = date.getUTCDate();
    const day = (d < 10) ? '0' + d : d;
    const m = date.getUTCMonth() + 1;
    const month = (m < 10) ? '0' + m : m;
    const year = date.getUTCFullYear();
    const h = date.getUTCHours();
    const hour = (h < 10) ? '0' + h : h;
    const mi = date.getUTCMinutes();
    const minute = (mi < 10) ? '0' + mi : mi;
    const sc = date.getUTCSeconds();
    const second = (sc < 10) ? '0' + sc : sc;
    const loctime = month + day + hour + minute + year + '.' + second;

    document.getElementById('localTime').value = loctime;

  }

Unfortunatelly when I submit the comment , I get the following error

ERROR in src/app/user-profile/user-profile.component.ts(75,21): error TS2365: Operator '+' cannot be applied to types 'string | number' and 'string | number'.
src/app/user-profile/user-profile.component.ts(77,42): error TS2339: Property 'value' does not exist on type 'HTMLElement'.

what do I need to change to get what I want??

Answer 1

You can try this code

const loctime = `${year}-${month}-${day}T${hour}:${minute}:${second}`;
// output "2018-10-27T10:26:32"

Instead of using Javascript Way, try to use Angular way

<input type="hidden" id="localTime" name="localTime" formControlName="localTime">

this. addForm.get('localTime').setValue(loctime);

Note: we need to use back-tick(``) instead of single quote ('').