C#判断一个String是否为数字类型

                return false;
            }
            else
            {
                haveDot = true;
            }
        }
        else if (i == 0)
        {
            if (inString[i] != '+' && inString[i] != '-')
            {
                return false;
            }
        }
        else
        {
            return false;
        }
        if (i > 20)
        {
            return false;
        }
    }
    return haveNumber;
}

 

方案四：改写vb的IsNumeric源代码(执行效率不高)

 

复制代码 //主调函数
public static bool IsNumeric(object Expression)
{
      bool flag1;
      IConvertible convertible1 = null;
      if (Expression is IConvertible)
      {
            convertible1 = (IConvertible) Expression;
      }
      if (convertible1 == null)
      {
            if (Expression is char[])
            {
                  Expression = new string((char[]) Expression);
            }
            else