isNum method

bool isNum(
  1. String s
)

Checks if string is int or double. 检查字符串是int还是double

Implementation

bool isNum(String s) {
  if (s.isNull) {
    return false;
  }
  var parseNum = num.tryParse(s);
  if (parseNum.isNull) {
    return false;
  }
  return parseNum is num;
}