C#字符串转换为数字的4种方法

判断C#中的字符串是否是数字,如果是转换成int类型

1.通过正则表达式(可以判断正数和负数)

public int IsNumeric(string str)
        {
            int i;
            if (str != null && System.Text.RegularExpressions.Regex.IsMatch(str, @"^-?\d+$"))
                i = int.Parse(str);
            else
                i = -1;
            return i;
        }

 

2.通过字符

　

        ///  
        /// 判断是否是数字 
        ///  
        ///  
        ///  
        private bool IsNumeric(string number)
        {
            try
            {
                for (int i = 0; i < number.Length; i++)
                {
                    if (number < '0' || number > '9')
                    {
                        return false;
                    }
                }
                return true;
            }
            catch
            {
                return false;
            }
        }

 

3.通过char.IsNumber方法

 

　/// 判断是否是数字 
        ///  
        ///  
        ///  
        private bool IsNumeric(string number)
        {
            try
            {
                for (int i = 0; i < number.Length; i++)
                {
                    if (!char.IsNumber(number, i))
                    {
                        return false;
                    }
                }
                return true;
            }
            catch
            {
                return false;
            }
        }

 

4.通过try,catch()

　　

        /// 判断是否是数字 
        ///  
        ///  
        ///  
        private bool IsNumeric(string number)
        {
            try
            {
                int.Parse(number);
                return true;
            }
            catch
            {
                return false;
            }
        }