Get current value when change select option - Angu

问题:

I'm writing an angular2 component and am facing this problem.

Description: I want to push an option value in select selector to its handler when the (change) event is triggered.

Such as the below template:

<select (change)="onItemChange(<!--something to push-->)">
    <option *ngFor="#value of values" value="{{value.key}}">{{value.value}}</option>
</select>

Component Class:

export Class Demo{

  private values = [
     {
        key:"key1",
        value:"value1"
     },
     {
        key:"key2",
        value:"value2"
     }
  ]

  constructor(){}
  onItemChange(anyThing:any){
     console.log(anyThing); //Here I want the changed value
  }
}

How can I get the value(without using jquery) ?

回答1:

There is a way to get the value from different options. check this plunker

component.html

 <select class="form-control" #t (change)="callType(t.value)">
  <option *ngFor="#type of types" [value]="type">{{type}}</option>
</select>

component.ts

    this.types = [ 'type1', 'type2', 'type3' ];
   this.order = {
      type: 'type1'          
  };  

  callType(value){
    console.log(value);
    this.order.type=value;
  }

回答2:

In angular 4, this worked for me

template.html

<select (change)="filterChanged($event.target.value)">
<option *ngFor="let type of filterTypes" [value]="type.value">{{type.display}}
</option>
</select>

component.ts

export class FilterComponent implements OnInit {

selectedFilter:string;
   public filterTypes = [
   {value:'percentage', display:'percentage'},
  {value:'amount', display:'amount'},
  ];

   constructor() { 
   this.selectedFilter='percentage';
   }

   filterChanged(selectedValue:string){
   console.log('value is ',selectedValue);

   }

  ngOnInit() {
  }

  }

回答3:

Checkout this working Plunker

<select (change)="onItemChange($event.target.value)">
    <option *ngFor="#value of values" [value]="value.key">{{value.value}}</option>
</select>

回答4:

For me, passing ($event.target.value) as suggested by @microniks did not work. What worked was ($event.value) instead. I am using Angular 4.2.x and Angular Material 2

<select (change)="onItemChange($event.value)">
    <option *ngFor="#value of values" [value]="value.key">
       {{value.value}}
    </option>
</select>

回答5:

You can Use ngValue. ngValue passes sting and object both.

Pass as Object:

<select (change)="onItemChange($event.value)">
    <option *ngFor="#obj of arr" [ngValue]="obj.value">
       {{obj.value}}
    </option>
</select>

Pass as String:

<select (change)="onItemChange($event.value)">
    <option *ngFor="#obj of arr" [ngValue]="obj">
       {{obj.value}}
    </option>
</select>

回答6:

Template:

<select class="randomClass" id="randomId" (change) = 
"filterSelected($event.target.value)">

<option *ngFor = 'let type of filterTypes' [value]='type.value'>{{type.display}} 
</option>

</select>

Component:

public filterTypes = [{
  value : 'New', display : 'Open'
},
{
  value : 'Closed', display : 'Closed'
}]


filterSelected(selectedValue:string){
  console.log('selected value= '+selectedValue)

}