empty static method

String? empty(
  1. String? val, {
  2. String? tipText,
})

空白字符校验

val 需要校验则字符 tipText 校验提示文字

Implementation

static String? empty(String? val, {String? tipText}) {
  if (val is! String || val.isEmpty) {
    return tipText ?? '请输入';
  }
  return null;
}