How to prevent from data-target and routerLink to open a new window?

Question

Each time I am clicking on the a tag the browser opens a new window. How to prevent this kind of behavior? I have also tried to put write an href #a instead of the data-target but it's not collapsing. (with data-target it is collapsing on the new window)

This is my code:

<nav>
 <ul>
  <li routerLinkActive="active">
    <a data-target=#a data-toggle="collapse" routerLink="device-tools" aria-
       expanded="false"><i class="fa fa-cogs" aria-hidden="true"></i>Device tools</a>
    <ul class="collapse list-unstyled" id="a">
      <li routerLinkActive="active"><a routerLink="protocol-group">Protocol group</a></li>
      <li routerLinkActive="active"><a routerLink="protocol">Protocol</a></li>
    </ul>
  </li>
 </ul>
</nav>

Answer 1

删除此行data-target=#a

Answer 2

In my case what I have done was to wrap the router link with another href :

<a href="#" data-toggle="collapse" data-target="#one">
    <a [routerLink]='["/"]' (click)='collapse()'>Home</a>
</a>