# PasswordInput 密码输入框

### 介绍

带网格的输入框组件，可以用于输入支付密码、短信验证码等，通常与[数字键盘](#/zh-CN/number-keyboard)组件配合使用

### 引入

```js
import { createApp } from 'vue';
import { PasswordInput, NumberKeyboard } from 'vant';

const app = createApp();
app.use(PasswordInput);
app.use(NumberKeyboard);
```

## 代码演示

### 基础用法

```html
<!-- 密码输入框 -->
<van-password-input
  :value="value"
  info="密码为 6 位数字"
  :focused="showKeyboard"
  @focus="showKeyboard = true"
/>
<!-- 数字键盘 -->
<van-number-keyboard
  :show="showKeyboard"
  @input="onInput"
  @delete="onDelete"
  @blur="showKeyboard = false"
/>
```

```js
export default {
  data() {
    return {
      value: '123',
      showKeyboard: true,
    };
  },
  methods: {
    onInput(key) {
      this.value = (this.value + key).slice(0, 6);
    },
    onDelete() {
      this.value = this.value.slice(0, this.value.length - 1);
    },
  },
};
```

### 自定义长度

```html
<van-password-input
  :value="value"
  :length="4"
  :gutter="15"
  :focused="showKeyboard"
  @focus="showKeyboard = true"
/>
```

### 明文展示

```html
<van-password-input
  :value="value"
  :mask="false"
  :focused="showKeyboard"
  @focus="showKeyboard = true"
/>
```

### 错误提示

通过`error-info`属性可以设置错误提示信息，例如当输入六位时提示密码错误

```html
<!-- 密码输入框 -->
<van-password-input
  :value="value"
  :error-info="errorInfo"
  :focused="showKeyboard"
  @focus="showKeyboard = true"
/>
<!-- 数字键盘 -->
<van-number-keyboard
  :show="showKeyboard"
  @input="onInput"
  @delete="onDelete"
  @blur="showKeyboard = false"
/>
```

```js
export default {
  data() {
    return {
      value: '123',
      showKeyboard: true,
      errorInfo: '',
    };
  },
  methods: {
    onInput(key) {
      this.value = (this.value + key).slice(0, 6);
      if (this.value.length === 6) {
        this.errorInfo = '密码错误';
      } else {
        this.errorInfo = '';
      }
    },
    onDelete() {
      this.value = this.value.slice(0, this.value.length - 1);
    },
  },
};
```

## API

### Props

| 参数 | 说明 | 类型 | 默认值 |
| --- | --- | --- | --- |
| value | 密码值 | _string_ | `''` |
| info | 输入框下方文字提示 | _string_ | - |
| error-info | 输入框下方错误提示 | _string_ | - |
| length | 密码最大长度 | _number \| string_ | `6` |
| gutter | 输入框格子之间的间距，如 `20px` `2em`，默认单位为`px` | _number \| string_ | `0` |
| mask | 是否隐藏密码内容 | _boolean_ | `true` |
| focused `v2.1.8` | 是否已聚焦，聚焦时会显示光标 | _boolean_ | `false` |

### Events

| 事件名 | 说明             | 回调参数 |
| ------ | ---------------- | -------- |
| focus  | 输入框聚焦时触发 | -        |
