Angular 2アプリケーションでTypeScriptを使用して他のドロップダウン値に基づいてドロップダウン値を表示する方法
開発中ですangular 2アプリケーション、現在のプロジェクトでは、年、メーカー、モデルに基づいてドロップダウン値を表示する機能が必要です。たとえば、ホンダを選択し、モデルドロップダウンにホンダモデルのみを表示する場合。
デフォルトでは、年、メーカー、モデルの完全なデータをバインドします。
これが私の見解です。
VehicleComponent.html
<div class="row form-group">
<div class="col-md-3">
<label class="control-label">Year*</label><br />
<select friendly-name="Year" id="year" name="year" class="col-md-6 form-control" ng-required="true" onchange='OnChange()' >
<option>Select</option>
<option *ngFor='let type of lookupdetailsvehicleyearinfo'>{{type.LookupValue}}</option>
</select>
</div>
<div class="col-md-3">
<label class="control-label">Make*</label><br />
<select friendly-name="Make" class="col-md-6 form-control" ng-required="true" >
<option>Select</option>
<option *ngFor='let type of lookupdetailsvehiclemakeinfo'>{{type.LookupValue}}</option>
</select>
</div>
<div class="col-md-3">
<label class="control-label">Model*</label>
<select friendly-name="Model" class="col-md-6 form-control" ng-required="true" >
<option>Select</option>
<option *ngFor='let type of lookupdetailsvehiclemodelinfo'>{{type.LookupValue}}</option>
</select>
</div>
</div>
上記のデータはMy Own APIから取得します。
上記の機能のためにangular 2アプリケーションでTypeScriptコードを書く方法を教えてください。
必要なのは、選択入力のchangeイベントを追跡し、別の選択入力のソースを変更することだけです。 Angular2が残りを行います。
選択したvalueを使用：
@Component({
selector: 'my-app',
template: `
<div>
<h2>Hello {{name}}</h2>
<select (change)="firstDropDownChanged($event.target.value)" >
<option>Select</option>
<option *ngFor='let v of _values1'>{{ v }}</option>
</select>
<select >
<option>Select</option>
<option *ngFor='let v of _values2'>{{ v }}</option>
</select>
</div>
`,
})
export class App {
name:string;
private _values1 = ["1", "2", "3"];
private _values2 = [];
constructor() {
this.name = 'Angular2'
}
firstDropDownChanged(val: any) {
console.log(val);
if (val == "1") {
this._values2 = ["1.1", "1.2", "1.3"];
}
else if (val == "2") {
this._values2 = ["2.1", "2.2", "2.3"];
}
else if (val == "3") {
this._values2 = ["3.1", "3.2", "3.3"];
}
else {
this._values2 = [];
}
}
}
ライブデモ： https://plnkr.co/edit/GDXsPt4aiS7vus6oPvuU?p=preview
[〜＃〜] update [〜＃〜]
または、selectedIndex：を使用できます（-1最初の「選択」項目を作成します。
@Component({
selector: 'my-app',
template: `
<div>
<h2>Hello {{name}}</h2>
<select (change)="firstDropDownChanged($event.target.selectedIndex - 1)" >
<option>Select</option>
<option *ngFor="let v of _values1">{{ v.val }}</option>
</select>
<select >
<option>Select</option>
<option *ngFor='let v of _values2'>{{ v }}</option>
</select>
</div>
`,
})
export class App {
name:string;
private _values1 = [
{ id: 1, val: "huhu" },
{ id: 2, val: "val2" },
{ id: 3, val: "yep" },
{ id: 4, val: "cool" }
];
private _values2 = [];
constructor() {
this.name = 'Angular2'
}
firstDropDownChanged(val: any) {
const obj = this._values1[val];
console.log(val, obj);
if (!obj) return;
if (obj.id == 1) {
this._values2 = ["1.1", "1.2", "1.3"];
}
else if (obj.id == 2) {
this._values2 = ["2.1", "2.2", "2.3"];
}
else if (obj.id == 3) {
this._values2 = ["3.1", "3.2", "3.3"];
}
else {
this._values2 = [];
}
}
}
Ng5-Dynamic Selectoption-国を選択するためのドロップダウンメニュー、次に州、次に地区
template.html
<div>
<h2>Hello country/ state/ cities </h2>
<select (change)="countryChange($event)" >
<option>Select</option>
<option *ngFor="let c of countries" [ngValue]="c.country">{{ c.country }}</option>
</select>
<select (change)="statesChange($event)">
<option>Select</option>
<option *ngFor='let state of states' [ngValue]="state.name">{{ state.name }}</option>
</select>
<select >
<option>Select</option>
<option *ngFor='let city of cities' [ngValue]="city">{{ city }}</option>
</select>
</div>
component.ts
var countries= [{
"country": "Afghanistan",
"states": [
{ "name":"Nurestan", "cities":["c1", "c2", "c3"] },
{ "name":"Oruzgan", "cities":["orc1", "oruc2", "oruc3"] },
{ "name":"Panjshir", "cities":["3c1", "3c2", "3c3"] }
]
},
{
"country": "Albania",
"states": [
{ "name": "Korce" , "cities":["c1", "c2", "c3"] },
{ "name": "Kukes", "cities":["orc1", "oruc2", "oruc3"] },
{ "name": "Lezhe","cities":["orc1", "oruc2", "oruc3"]},
{ "name": "Shkoder", "cities":["orc1", "oruc2", "oruc3"]},
{ "name": "Tirane","cities":["orc1", "oruc2", "oruc3"]}
]
},
{
"country": "Antarctica",
"states": []
}
]
states= []; cities = [];
countryChange(e){
console.log(e.target.value)
this.countries.filter(element => {
if(element.country == e.target.value){
console.log(element.states[0],"first state")
this.states = element.states;
}
});
this.cities = []
}
statesChange(evt){
console.log(evt.target.value,this.states)
this.states.filter( element =>{
if(element.name == evt.target.value){
this.cities = element.cities;
}
})
}