如何使“ Previos”按钮消失

Question

我想在6号角上实现分页。如果偏移为0，如何阻止“ Previos”（或更确切地说，使其完全消失），否则必须再次激活。

html按钮：

<div *ngIf="!loading; else loader">
   <div *ngIf="notes.length !== 0; else empty">
     ......
     <button mat-button (click)="Previos()"  *ngIf="!loading; else loader">Previos</button>
     <button mat-button (click)="Next()"  [ngStyle]="{display: noMore ? 'none' : 'inline-block'}" *ngIf="!loading; else loader">Next</button>
   </div>
</div>

ts：

const STEP = 10
const LIMIT = 10

nSub: Subscription
notes: Note[]
loading = false
noMore = false
limit = LIMIT
offset = 0

private loadNotes() {
  const params = {
    limit: this.limit,
    offset: this.offset
  }
  this.loading = true;
  this.nSub = this.noteService.fetch(params, this.notes_id).subscribe(
    notes => {
      this.notes = notes 
      this.noMore = notes .length < STEP
      this.loading = false
    }
  );
}

Next() {
  this.offset += STEP
  this.loading = true
  this.loadNotes()
}

Previos() {
  this.offset -= STEP
  this.loading = true
  this.loadNotes()
}

Answer 1

您不能添加到ngIf，偏移量== 0？

Previos