message: [bugfix] Filed number type value filter
diff: class="van-field__control"
  :type="type"
  :value="value"
  + @keypress="onKeypress"
  @input="onInput"
  @focus="$emit('focus')"
  @blur="$emit('blur')"
  @@ -111,6 +112,17 @@ export default {
  this.onIconClick();
  },
  + onKeypress(event) {
  + if (this.type === 'number') {
  + const { keyCode } = event;
  + const allowPoint = this.value.indexOf('.') === -1;
  + const isValidKey = (keyCode >= 48 && keyCode <= 57) || (keyCode === 46 && allowPoint);
  + if (!isValidKey) {
  + event.preventDefault();
  + }
  + }
  + },
  +
  adjustSize() {
  const el = this.$refs.textarea;
  el.style.height = 'auto';
  