我有一个包含数字值的html输入框的指令.当用户将数字粘贴到文本框中时,我有一个“清理”数字的指令(剥离逗号,美元符号等).清洁代码似乎工作正常,但即使文本框显示清理后的值,我的模型也没有使用清理后的值更新.
如何使用新值更新模型？
这是一个精简的例子：
app.ts
@Component(
@Component({
selector : 'my-app',template : `
<div>
<br/>
<br/>
<p>Stack Overflow person - give focus to text Box and then lose focus by clicking elsewhere in the screen. <br/>The model is not updated.</p>
<br/>Model value: {{ balanceAmount }}
<br/>
<br/>
<input type="text" [(ngModel)]="balanceAmount" myCurrencyFormatter /><br/>
</div>
`,})
export class App {
name:string;
constructor(private mycurpipe: MyCurrencyPipe) {
this.balanceAmount = 1234567.89;
}
}
货币格式化,Directive.ts
@Directive({ selector: "[myCurrencyFormatter]" })
export class MyCurrencyFormatterDirective implements OnInit {
private el: any;
constructor(
private elementRef: ElementRef,private currencyPipe: MyCurrencyPipe
) {
this.el = this.elementRef.nativeElement;
}
ngOnInit() {
this.el.value = this.currencyPipe.transform(this.el.value);
}
@HostListener("focus",["$event.target.value"])
onFocus(value) {
this.el.value = this.currencyPipe.parse(value); // opossite of transform
}
@HostListener("blur",["$event.target.value"])
onBlur(value) {
this.el.value = this.cleanNumber(value); //"987654" ;//this.currencyPipe.transform(value);
}
cleanNumber (value: number) {
return 8888888; // clean logic goes here,removed for plunk example
}
}
解决方法
您需要为模型添加发射器.这是在Angular 2中实现双向绑定的方法.看看@Output()行ngModelChange = new EventEmitter();以及我如何使用此变量向调用者发出更改.
import { Directive,HostListener,ElementRef,OnInit,EventEmitter,Output } from "@angular/core";
import { MyCurrencyPipe } from "./my-currency.pipe";
@Directive({ selector: "[myCurrencyFormatter]" })
export class MyCurrencyFormatterDirective implements OnInit {
private el: any;
@Output() ngModelChange = new EventEmitter();
constructor(
private elementRef: ElementRef,["$event.target.value"])
onFocus(value) {
this.el.value = this.currencyPipe.parse(value); // oposite of transform
this.ngModelChange.emit(this.el.value);
}
@HostListener("blur",["$event.target.value"])
onBlur(value) {
this.el.value = this.cleanNumber(value); //"987654" ;//this.currencyPipe.transform(value);
this.ngModelChange.emit(this.el.value);
}
cleanNumber (value: number) {
return 8888888;
}
}
