Angular2表单验证错误，来自组错误

Question

如果我在表单验证中出错，请帮助我

customerGroupValidator: FormGroup = null;
    constructor() {
        var _builder = new FormBuilder();
        this.customerGroupValidator = _builder.group({
            EmpName: ['', [Validators.required, Validators.minLength(2), Validators.maxLength(4)]],

        })
    }
 IsValid(): boolean{
        return this.customerGroupValidator.valid;
    }

Html代码

这里我得到错误，因为FormGroup需要一个FormGroup实例。即使我添加[formGroup] =＆＃34; custobj.customerGroupValidator＆＃34;

，请帮助我在哪里犯了错误

<form  [formGroup]="custobj.customerGroupValidator">
            <div class="form-group">
                <label for="name">Name</label>
                <input type="text" class="form-control" formControlName="EmpName" [(ngModel)]="custobj.EmpName" />
<button type="submit" class="btn btn-success btn-block" [disabled]="!custobj.IsValid">Submit</button>

        </form>