Angular mat-autocomplete：如何显示选项名称而不是输入中的值

Question

I'm using the mat-autocomplete widget under my Angular app :

    <mat-form-field class="col-md-3" color="warn">
                <input type="text"
                       id="libelleShop"
                       #inputSelectShop
                       placeholder="Selectionner la boutique"
                       matInput
                       formControlName="libelleShop"
                       ngDefaultControl
                       [matAutocomplete]="auto">
                <mat-autocomplete #auto="matAutocomplete"" 
               (optionSelected)="onShopSelectionChanged($event)">
                  <mat-option *ngFor="let shop of shopData" [value]="shop.value">
                    {{shop.name}}
                  </mat-option>
                </mat-autocomplete>
   </mat-form-field>

my Shop data is like this :

shopData = [
    {name: 'AAA' , value :'11'},
    {name: 'BBB', value :'22'},
    {name: 'CCC', value : '33'}
  ];

Like this - options are displayed by name , but when selection the input displaysit by the value not the name .

Knowing that i need the value for other treatment and i won't change the [value] in the mat-automplete .

How may i take reference for the name to the input ??

Suggestions ??

Answer 1

You can use the displayWith attribute of Mat autocomplete and pass in a function that will return the desired formatted string.

In your example:

 displayFn(shop: Shop): string { return shop.name; }

 <mat-autocomplete #auto="matAutocomplete"" (optionSelected)="onShopSelectionChanged($event)" [displayWith]="displayFn"> <mat-option *ngFor="let shop of shopData" [value]="shop"> {{shop.name}} </mat-option> </mat-autocomplete>

Answer 2

Simple way by using option id mayby useful:

<mat-autocomplete #auto="matAutocomplete" (optionSelected)="onShopSelectionChanged($event)">
  <mat-option *ngFor="let shop of shopData" [value]="shop.name" [id]="shop.value">
    {{shop.name}}
  </mat-option>
</mat-autocomplete>

and read value & name in the function:

onShopSelectionChanged(event) {
    const selectedValue = event.option.id;
    console.log(selectedValue);
    const selectedName = event.option.value;
    console.log(selectedName);
}

Answer 3

Because you don't want to change [value]="shop.value" , your only resort is to lookup the name based on value in a function used with the displayWith feature:

<mat-autocomplete ... [displayWith]="getShopName" ... >


getShopName(value) {
    const results = this.shopData.filter(shop => shop.value === value);
    if (results.length) {
        return results[0].name;
    }
    return value;
}

Answer 4

You can use FormControl on input tag and can change the value of this form-control using patchValue method.

Use (onSelectionChange)="onEnter($event)" and find the selectedArray option using the selected value, and from that selected option object update the value of input with any of the options key.

Html :

<form class="example-form">
  <mat-form-field class="example-full-width">
    <input #stateInput (keyup)="0" matInput placeholder="State" 
     aria-label="State" [matAutocomplete]="auto" [formControl]="stateCtrl">
    <mat-autocomplete #auto="matAutocomplete">
      <mat-option (onSelectionChange)="stateInput.value !=undefined && 
      onEnter($event)" *ngFor="let state of filteredStates | async"
      [value]="state.name">
        <img style="vertical-align:middle;" aria-hidden 
         src="{{state.flag}}" height="25" />
        <span>{{ state.name }}</span> |
        <small>Population: {{state.population}}</small>
      </mat-option>
    </mat-autocomplete>
  </mat-form-field>

---

Ts file :

 onEnter(evt: any){
    const selectedState =  this.states.find(state =>
      state.name.toLowerCase()==evt.source.value.toLowerCase());
    if (evt.source.selected) {
      console.log(selectedState);
      if(selectedState) {
      setTimeout(()=>{
        this.stateCtrl.patchValue(selectedState.population);
      }, 0);
      }
    }
  }

Stackblitz Demo with other data