感谢您的帮助,并提前感谢所有解决方案。我创建了一个 FormGroup 并希望通过循环将 FormControls 添加到 FormGroup 中。本教程来自 Matt Thornton 使用 Angular 构建真实网站。在 Angular 17 中,动态创建的 FormControls 是如何做到这一点的? 我在下面留下了错误消息。
Overload 1 of 2, '(this: FormGroup<{ [key: string]: AbstractControl<any, any>; }>, name: string, control: AbstractControl<any, any>, options?: { emitEvent?: boolean | undefined; } | undefined): void', gave the following error.
The 'this' context of type 'FormGroup<{ roomName: FormControl<string | null>; location: FormControl<string | null>; }>' is not assignable to method's 'this' of type 'FormGroup<{ [key: string]: AbstractControl<any, any>; }>'.
Type '{ [key: string]: AbstractControl<any, any>; }' is missing the following properties from type '{ roomName: FormControl<string | null>; location: FormControl<string | null>; }': roomName, location
Overload 2 of 2, '(name: "roomName" | "location", control: FormControl<string | null>, options?: { emitEvent?: boolean | undefined; } | undefined): void', gave the following error.
Argument of type '`layout${string}`' is not assignable to parameter of type '"roomName" | "location"'. [plugin angular-compiler]
src/app/admin/rooms/room-edit/room-edit.component.ts:37:20:
37 │ this.roomForm.addControl(`layout${layout}`, new FormControl(
房间.ts:
export enum Layout {
THEATER = 'Theater',
USHAPE = 'U-Shape',
BOARD = 'Board Meeting'
}
房间编辑.component.ts:
import { Component, Input, OnInit } from '@angular/core';
import { Layout, LayoutCapacity, Room } from '../../../model/room';
import { FormControl, FormGroup, Validators } from '@angular/forms';
@Component({
selector: 'app-room-edit',
templateUrl: './room-edit.component.html',
styleUrl: './room-edit.component.css'
})
export class RoomEditComponent implements OnInit{
@Input()
room: Room;
layouts = Object.keys(Layout);
layoutEnum = Layout;
layoutTypes: Array<string> = Object.keys(Layout).filter(key => isNaN(+key));
roomForm = new FormGroup(
{
roomName : new FormControl('roomName'),
location: new FormControl('location'),
}
);
constructor() {
this.room = new Room();
}
ngOnInit(): void {
this.roomForm.patchValue({
roomName: this.room.name,
location: this.room.location
});
for (const layout of this.layouts) {
this.roomForm.addControl(`layout${layout}`, new FormControl(`layout${layout}`));
}
}
onSubmit() {
this.room.name = this.roomForm.controls['roomName'].value ?? '';
this.room.location = this.roomForm.value['location'] ?? '';
this.room.capacities = new Array<LayoutCapacity>();
console.log(this.room);
}
getLayoutByKey(layoutKey: string): Layout {
return this.layoutEnum[layoutKey as keyof typeof Layout];
}
}
第 1 步:定义您的枚举
export enum UserRole {
Admin = 'Admin',
User = 'User',
Guest = 'Guest'
}
第 2 步:创建 FormGroup 并将枚举添加为 FormControl
import { FormBuilder, FormGroup } from '@angular/forms';
import { UserRole } from './user-role.enum';
export class MyComponent {
form: FormGroup;
roles = UserRole; // reference Enum for easy access in the template
roleOptions = Object.values(UserRole); // get Enum values for UI options
constructor(private fb: FormBuilder) {
this.form = this.fb.group({
role: [UserRole.User] // set default value
});
}
}
第3步:在模板中绑定Enum选项
<form [formGroup]="form">
<label for="role">User Role:</label>
<select id="role" formControlName="role">
<option *ngFor="let role of roleOptions" [value]="role">{{ role }}</option>
</select>
</form>