问题
I need to select two different date formats (YYYY-MM-DD and YYYY-MM) in two mat datepicker fields in one component view.
I'm using angular 6.0.3 and material 6.4.7.
I configured datepicker format to YYYY-MM-DD in app module using MAT_DATE_FORMATS and it works globally but I need to override this format to YYYY-MM in a few datepicker fields as I wrote above. Unfortunatelly I have no idea how I can achieve this.
Could You help me please?
Parts of my code:
        import { Component, OnInit, ViewChild } from '@angular/core';
    import { FormGroup, FormControl } from '@angular/forms';
    @Component({
      selector: 'app-invoice-list',
      templateUrl: './invoice-list.component.html',
      styleUrls: ['./invoice-list.component.css']
    })
    export class InvoiceListComponent {
      filterForm: FormGroup;
      @ViewChild('month_picker') month_picker;
      constructor() {
        this.filterForm = new FormGroup({
          assigned_date_from: new FormControl(),
          assigned_date_to: new FormControl(),
          assigned_month: new FormControl(),
        });
      }
    }
<div class="container" [formGroup]="filterForm">
  <div class="container" fxLayout="row" fxLayout.xs="column" fxLayoutWrap fxLayoutGap="0.5%" fxLayoutAlign="start">
      <div fxFlex="32%">
        <mat-form-field>
            <input matInput [matDatepicker]="date_from_picker" (focus)="date_from_picker.open()" formControlName="assigned_date_from" placeholder="Date from">
            <mat-datepicker-toggle matSuffix [for]="date_from_picker"></mat-datepicker-toggle>
            <mat-datepicker #date_from_picker></mat-datepicker>
        </mat-form-field>
      </div>
      <div fxFlex="32%">
        <mat-form-field>
            <input matInput [matDatepicker]="date_to_picker" (focus)="date_to_picker.open()" formControlName="assigned_date_to" placeholder="Date to">
            <mat-datepicker-toggle matSuffix [for]="date_to_picker"></mat-datepicker-toggle>
            <mat-datepicker #date_to_picker></mat-datepicker>
          </mat-form-field>
      </div>
      <!-- In below input I want month year format - YYYY-MM - so different than default format in above fields -->
      <div fxFlex="32%">
          <mat-form-field>
              <input matInput [matDatepicker]="month_picker" (focus)="month_picker.open()" formControlName="assigned_month" placeholder="Month">
              <mat-datepicker-toggle matSuffix [for]="month_picker"></mat-datepicker-toggle>
              <mat-datepicker #month_picker></mat-datepicker>
            </mat-form-field>
        </div>
    </div>
</div>
    回答1:
Please try this. In your Html
        <mat-form-field>
          <input matInput [matDatepicker]="month_picker" (focus)="month_picker.open()" [value] = "selectedMonth" placeholder="Month">
          <mat-datepicker-toggle matSuffix [for]="month_picker"></mat-datepicker-toggle>
          <mat-datepicker #month_picker  
              startView="multi-year"
              (monthSelected)="chosenMonthHandler($event, month_picker)"></mat-datepicker>
        </mat-form-field>
In your .ts
    selectedMonth = new Date();
    chosenMonthHandler(normlizedMonth, datepicker) {
        var tempDate = JSON.stringify(normlizedMonth).replace("\"",'').split("-")
        var month = parseInt(tempDate[1])
        var year = month == 12?parseInt(tempDate[0])+1:parseInt(tempDate[0])
        var year = month == 12?parseInt(tempDate[0])+1:parseInt(tempDate[0])
        month = month == 12?1:month+1;
        this.selectedMonth = new Date(year + "-" + month)
        console.log(year + " " + month)
        datepicker.close();
      }
This works well.but show the selected date as 1 after select a month.But I think this fulfills your requirements.
回答2:
If you're looking for a way to have a couple static formats, it is possible.
Unfortunately, if you want to have it be dynamic based on a directive input (e.g. ) This won't work because there isn't currently a mechanism to tell the datepicker that the format has updated.
More information can be found here
回答3:
http://brickydev.com/angular-material-datepicker-with-many-custom-date-formats/
I found this link and this solution worked for me.
step 1: Create a directive
ng generate directive customDateFormat
step 2:
import { Directive } from '@angular/core';
import { MAT_DATE_FORMATS } from '@angular/material/core';
export const FORMAT = {
  parse: {
    dateInput: 'DD-MM-YYYY',
  },
  display: {
    dateInput: 'DD-MM-YYYY',
    monthYearLabel: 'MMM YYYY',
    dateA11yLabel: 'LL',
    monthYearA11yLabel: 'MMMM YYYY',
  },
};
@Directive({
  selector: '[appCustomeDateFormats]',
  providers: [{ provide: MAT_DATE_FORMATS, useValue: FORMAT }],
})
export class CustomeDateFormatsDirective {
  constructor() {}
}
step 3: use this directive in the template.
     <mat-form-field class="example-full-width" appCustomeDateFormats>
            <mat-label>Start Date</mat-label>
            <input
              matInput
              [matDatepicker]="startDate"
              formControlName="from_date"
            />
            <mat-datepicker-toggle
              matSuffix
              [for]="startDate"
            ></mat-datepicker-toggle>
            <mat-datepicker touchUi #startDate></mat-datepicker>
          </mat-form-field>
    来源:https://stackoverflow.com/questions/52677742/angular-material-6-datepicker-different-formats-in-same-component