el-input限制字符的输入

1.只支持数字

<el-input
  v-model="value"
  placeholder="请输入"
  clearable
  @input="value = value.replace(/[^\d]/g,'')">
</el-input>

2.持数字与小数，且保留小数后两位

<el-input
  v-model="value"
  placeholder="请输入"
  clearable
  @input="value = value.replace(/[^\d.]/g, '').replace(/\.{2,}/g, '.')
  .replace('.', '$#$').replace(/\./g, '').replace('$#$', '.')
  .replace(/^(\-)*(\d+)\.(\d\d).*$/, '$1$2.$3').replace(/^\./g, '')">
</el-input>

3.只支持英文大小写和数字

<el-input
  v-model="value"
  placeholder="请输入"
  clearable
  @input="value = value.replace(/[\W]/g, '')">
</el-input>

4.只支持汉字和字母

<el-input
  v-model="value"
  placeholder="请输入"
  clearable
  @input="value = value.replace(/[^\a-\z\A\u4E00-\u9FA5]/g,'')">
</el-input>

5.只支持正整数

<el-input
  v-model="value"
  placeholder="请输入"
  clearable
  onKeypress="return (/[\d]/.test(String.fromCharCode(event.keyCode)))">
</el-input>