angular2 template - ngSwitchWhen doesn't work when duplicate whens are written -


i learning angular2 using ng-book2 book , playing around built in directives. reading ngswitch , stumbled upon feature can write multiple ngswitchwhen same conditions following code:

   <ul [ngswitch]="choice">     <li *ngswitchwhen="1">first choice</li>     <li *ngswitchwhen="2">second choice</li>     <li *ngswitchwhen="3">third choice</li>     <li *ngswitchwhen="4">fourth choice</li>     <li *ngswitchwhen="2">second choice, again</li>     <li *ngswitchdefault>default choice</li>      </ul>

which output following result:

second choice

second choice, again

i wrote code below:

  <div [ngswitch]="myvar">         <div *ngswitchwhen="myvar==1">my var 1</div>         <div *ngswitchwhen="myvar==2">my var 2</div>         <div *ngswitchwhen="myvar==3">my var 3</div>         <div *ngswitchwhen="myvar==3">special feature of ng swtich</div>         <div *ngswitchdefault>my var {{myvar}}</div>     </div>

which not print output same conditions. thought code proper when saw *ngswitchwhen="myvar==3" found out mistake.

but strangely works except repeated conditions

is there difference between these 2 conditions?

*ngswitchwhen="2"

*ngswitchwhen="myvar==3"

which 1 use?

ngswitchwhen="2"

this expression checks value of switchcase against variable myvar(myvar=="6")

ngswitchwhen="myvar==3"

whereas expression evaluates myvar==(myvar==2) value inside parantheses return 1 if myvar 2 , 0 if not


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