Angular 2 延伸现有管道
示例
import { Pipe, PipeTransform } from '@angular/core';
import { DatePipe } from '@angular/common'
@Pipe({name: 'ifDate'})
export class IfDate implements PipeTransform {
private datePipe: DatePipe = new DatePipe();
transform(value: any, pattern?:string) : any {
if (typeof value === 'number') {return value}
try {
return this.datePipe.transform(value, pattern)
} catch(err) {
return value
}
}
}