如果我输入 21121997 它应该在日期文本框中转换为 21/12/1997。如果我给 01012012 那么它应该转换为 01/01/2012。那是 dd/mm/yyyy 格式。怎么做?html代码-->
<div class="p-col-12 p-mb-2 p-lg-6 p-mb-lg-0 w-100">
<mat-form-field appearance="outline" fxFlex="100">
<mat-label>First Name</mat-label>
<input matInput formControlName="firstname" name="firstname" id="firstname">
</mat-form-field>
</div>
<div class="p-col-12 p-mb-2 p-lg-6 p-mb-lg-0 w-100">
<mat-form-field appearance="outline" fxFlex="100">
<mat-label>Date Of Birth</mat-label>
<input matInput formControlName="date" [matDatepicker]="picker2" >
<mat-datepicker-toggle matSuffix [for]="picker2"></mat-datepicker-toggle>
<mat-datepicker #picker2 color="primary"></mat-datepicker>
</mat-form-field>
</div>
ts 代码-->
individualCustForm = this.fb.group({
firstname: [undefined, [Validators.required, Validators.pattern('[a-zA-Z]*')]],
date: [undefined, [Validators.required]]
})