EtInput example:

- 根据正则过滤用户输入

```vue
<template>
  <div>
    <el-form ref="form" :model="form" :rules="rules" style="width: 500px;">
      <el-form-item label="只支持输入数字" prop="value">
        <et-input v-model="form.value" :filter-reg="/[^0-9]/g"></et-input>
      </el-form-item>
      <el-form-item label="只支持输入数字和字母" prop="value1">
        <et-input v-model="form.value1" :filter-reg="/[^A-Za-z0-9]/g"></et-input>
      </el-form-item>
      <el-form-item label="只支持输入中文" prop="value2">
        <et-input v-model="form.value2" :filter-reg="/[^\u4e00-\u9fa5]/g"></et-input>
      </el-form-item>
      <el-form-item>
        <el-button type="primary" @click="submit">提交</el-button>
      </el-form-item>
    </el-form>
  </div>
</template>

<script>
export default {
  data() {
    return {
      form: {
        value: '',
        value1: '',
        value2: '',
      },
      rules: {
        value: [
          {
            required: true,
            message: '请输入数字',
            trigger: 'change'
          }
        ],
        value1: [
          {
            required: true,
            message: '请输入数字和字母',
            trigger: 'change'
          }
        ],
        value2: [
          {
            required: true,
            message: '请输入中文',
            trigger: 'change'
          }
        ],
      }
    }
  },
  methods: {
    submit() {
      this.$refs.form.validate()
    }
  }
}
</script>

<style></style>
```