Javascript 在列表中选择操纵

我有一个列表，一旦我选择了列表中的最后一项，我希望它总是选择第一项

<ion-select interface="popover" [ngModel]="selecteduser._id" (ngModelChange)="selectUser($event)">
    <ion-option *ngFor="let user of users; let i = index" [value]="i" [selected]="isUserSelected[i]" (ionSelect)="selectUser(i)">
      </ion-content>{{ getUserNickname(user }} </ion-option>
    <ion-option  (ionSelect)="openConfigPage()" >Configuration</ion-option>
</ion-select>

有办法做到这一点吗

<ion-select interface="popover" [ngModel]="selecteduser._id" (ngModelChange)="selectUser($event)">
    <ion-option *ngFor="let user of users" [value]="user._id">
      </ion-content>{{ getUserNickname(user }} </ion-option>
    <ion-option  (ionSelect)="openConfigPage()" >Configuration</ion-option>
</ion-select>

<ion-select interface="popover" [ngModel]="selecteduser._id" (ngModelChange)="selectUser($event)">
    <ion-option *ngFor="let user of users; let i = index" [value]="i" [selected]="isUserSelected[i]" (ionSelect)="selectUser(i)">
      </ion-content>{{ getUserNickname(user }} </ion-option>
    <ion-option  (ionSelect)="openConfigPage()" >Configuration</ion-option>
</ion-select>

<ion-select interface="popover" [ngModel]="selecteduser._id" (ngModelChange)="selectUser($event)">
    <ion-option *ngFor="let user of users; let i = index" [value]="i" [selected]="isUserSelected[i]" (ionSelect)="selectUser(i)">
      </ion-content>{{ getUserNickname(user }} </ion-option>
    <ion-option  (ionSelect)="openConfigPage()" >Configuration</ion-option>
</ion-select>

---

有没有一种方法可以使用DOM执行此操作？

将isUserSelected声明为布尔数组，然后按如下方式填充它：

openConfigPage() {
    this.isUserSelected = this.users.map((e, i) => {
      return (i === 0) ? true : false; 
    });
    this.navCtrl.push(ConfigPage)
}

<ion-select interface="popover" [ngModel]="selecteduser._id" (ngModelChange)="selectUser($event)">
    <ion-option *ngFor="let user of users; let i = index" [value]="i" [selected]="isUserSelected[i]" (ionSelect)="selectUser(i)">
      </ion-content>{{ getUserNickname(user }} </ion-option>
    <ion-option  (ionSelect)="openConfigPage()" >Configuration</ion-option>
</ion-select>

然后在

html

侧使用

selected

属性，如下所示：

<ion-select interface="popover" [ngModel]="selecteduser._id" (ngModelChange)="selectUser($event)">
    <ion-option *ngFor="let user of users; let i = index" [value]="i" [selected]="isUserSelected[i]" (ionSelect)="selectUser(i)">
      </ion-content>{{ getUserNickname(user }} </ion-option>
    <ion-option  (ionSelect)="openConfigPage()" >Configuration</ion-option>
</ion-select>

---

了解更多信息。

有没有办法用这样的东西来做？document.getElementsByClassName（'somethin'）。selectIndex@julia456124645我认为在使用angular这样的库时，不建议直接进行DOM操作。错误：类型boolean[]不可分配给类型“boolean”@julia456124645您是否声明了

isUserSelected

as

isUserSelected:boolean[]=[]

？谢谢先生，获取错误参数未对齐：this.navCtrl.push（ConfigPage）

<ion-select interface="popover" [ngModel]="selecteduser._id" (ngModelChange)="selectUser($event)">
    <ion-option *ngFor="let user of users; let i = index" [value]="i" [selected]="isUserSelected[i]" (ionSelect)="selectUser(i)">
      </ion-content>{{ getUserNickname(user }} </ion-option>
    <ion-option  (ionSelect)="openConfigPage()" >Configuration</ion-option>
</ion-select>