如何在 Angular 9 的屏幕中间居中放置 <mat-card>

Question

* 我有一个<mat-card>，我想在我尝试过的屏幕中间居中，但它没有居中。它在toggle-device-toolbar 中应该看起来不错，因为它适用于手机，我需要一些帮助。我正在使用angular-material 和ng-bootstrap*

这是<mat-card>的代码

<div class="container ">
    <mat-card>
    <mat-radio-group aria-label="Select an option" [(ngModel)]="radio_btn">
        <mat-radio-button  [value]="true" >Admin</mat-radio-button>
        <mat-radio-button [value]="false">User</mat-radio-button>
    </mat-radio-group>   
        <div class="row justify-content-center" *ngIf="radio_btn==true;else form2">
            <form class="example-form " [formGroup]="loginForm" (ngSubmit)="send()">
                <mat-form-field class="example-full-width">
                    <input matInput formControlName="Identifier" placeholder="User" >
                </mat-form-field><br>
                <div *ngIf="loginForm.get('Identifier').hasError('Identifier') && loginForm.get('Identifier').touched">Introduce an email</div><br>
                <mat-form-field class="example-full-width">
                    <input matInput formControlName="Password" placeholder="Password" type="password">
                </mat-form-field><br>
                <div *ngIf="loginForm.get('Password').hasError('Password') && loginForm.get('Password').touched">Introduce the correctly password</div><br>
                <button mat-raised-button [disabled]="loginForm.invalid" class="colour_button " type="submit">Login 1</button>
            </form>
        </div>
</mat-card>
</div>

这就是现在的样子

Answer 1

我就是这样解决的

This is my css file

.center{
    width: 75%;
    margin: 10px auto;
  }

  .main-div{
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
  }

This is my html file

<div class="main-div">
    <mat-card class="z-depth center" flex="50" >
        <mat-radio-group aria-label="Select an option" [(ngModel)]="radio_btn">
            <mat-radio-button  [value]="true" >Admin</mat-radio-button>
            <mat-radio-button [value]="false">User</mat-radio-button>
        </mat-radio-group>   
            <div *ngIf="radio_btn==true;else form2">
                <form class="example-form " [formGroup]="loginForm" (ngSubmit)="send()">
                    <mat-form-field class="example-full-width">
                        <input matInput formControlName="Identifier" placeholder="User" >
                    </mat-form-field><br>
                    <div *ngIf="loginForm.get('Identifier').hasError('Identifier') && loginForm.get('Identifier').touched">Introduce an email</div><br>
                    <mat-form-field class="example-full-width">
                        <input matInput formControlName="Password" placeholder="Password" type="password">
                    </mat-form-field><br>
                    <div *ngIf="loginForm.get('Password').hasError('Password') && loginForm.get('Password').touched">Introduce the correctly password</div><br>
                    <button mat-raised-button [disabled]="loginForm.invalid" class="colour_button " type="submit">Login 1</button>
                </form>
            </div>
    </mat-card>
  </div>

Answer 2

你可以用Flexbox做到这一点

在你必须添加的组件样式中：

.container {
  display: flex; 
  align-items: center; 
  justify-content: center;
}

此外，如果您将 grid 更改为 flex，它也应该可以工作。

.container {
  display: grid; 
  align-items: center; 
  justify-content: center;
}