c#使用正则表达式（c# 正则表达式判断字符串是否全是数字）

废话不多说了，下面代码给大家介绍下利用正则表达式判断字符的方法，具体代码如下所示：

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 using System; using System.Text.RegularExpressions; using System.NET; namespace 正则表达式检测字符串 { class Program { static void Main(string[] args) { Console.WriteLine("请输入字符串："); string s = Console.ReadLine(); if (GF_IsOk.IsExistHanZi(s)) { Console.Write("包含汉字"); } else { Console.Write("不包含汉字"); } Console.ReadLine(); } } //判断部分 public class GF_IsOk { /// <summary> /// 判读是否是IP地址 /// </summary> /// <param name="in_str"></param> /// <returns></returns> public static bool IsIPStr(string in_str) { IPAddress ip; return IPAddress.TryParse(in_str, out ip); } /// <summary> /// 判断是否是数字 /// </summary> /// <param name="strNumber"></param> /// <returns></returns> public static bool IsNumber(string strNumber) { Regex objNotNumberPattern = new Regex("[^0-9.-]"); Regex objTwoDotPattern = new Regex("[0-9]*[.][0-9]*[.][0-9]*"); Regex objTwoMinusPattern = new Regex("[0-9]*[-][0-9]*[-][0-9]*"); String strValidRealPattern = "^([-]|[.]|[-.]|[0-9])[0-9]*[.]*[0-9]+$"; String strValidIntegerPattern = "^([-]|[0-9])[0-9]*$"; Regex objNumberPattern = new Regex("(" + strValidRealPattern + ")|(" + strValidIntegerPattern + ")"); return !objNotNumberPattern.IsMatch(strNumber) && !objTwoDotPattern.IsMatch(strNumber) && !objTwoMinusPattern.IsMatch(strNumber) && objNumberPattern.IsMatch(strNumber); } /// <summary> /// 判断是否是日期字符串 /// </summary> /// <param name="in_str"></param> /// <returns></returns> public static bool IsDateStr_yyyymmdd(string in_str) { if (in_str == "") return true; if (in_str.Length != 8) return false; return IsDateStr(in_str); } /// <summary> /// 判断是否是日期字符串 /// </summary> /// <param name="in_str"></param> /// <returns></returns> public static bool IsDateStr(string in_str) { if (in_str == "") return true; if (in_str.Length == 8) in_str = in_str.Substring(0, 4) + "-" + in_str.Substring(4, 2) + "-" + in_str.Substring(6, 2); DateTime dtDate; bool bValid = true; try { dtDate = DateTime.Parse(in_str); } catch (FormatException) { // 如果解析方法失败则表示不是日期性数据 bValid = false; } return bValid; } /// <summary> /// 判断字符串中是否包含汉字,有返回true 否则为false /// </summary> /// <param name="str"></param> /// <returns></returns> public static bool IsExistHanZi(string str) { Regex reg = new Regex(@"[\u4e00-\u9fa5]");//正则表达式 if (reg.IsMatch(str)) { return true; } else { return false; } } /// <summary> /// 字段串是否为Null或为""(空) /// </summary> /// <param name="str"></param> /// <returns></returns> public static bool IsStrNullOrEmpty(string str) { if (str == null || str.Trim() == string.Empty) return true; return false; } /// <summary> /// 返回文件是否存在 /// </summary> /// <param name="filename">文件名</param> /// <returns>是否存在</returns> public static bool IsFileExists(string filename) { return System.IO.File.Exists(filename); } /// <summary> /// 检测是否符合email格式 /// </summary> /// <param name="strEmail">要判断的email字符串</param> /// <returns>判断结果</returns> public static bool IsValidEmail(string strEmail) { return Regex.IsMatch(strEmail, @"^[\w\.]+([-]\w+)*@[A-Za-z0-9-_]+[\.][A-Za-z0-9-_]"); } public static bool IsValidDoEmail(string strEmail) { return Regex.IsMatch(strEmail, @"^@(( [0−9]1,3\.[0−9]1,3\.[0−9]1,3\.)|(([\w−]+\.)+))([a−zA−Z]2,4|[0−9]1,3)( ?)$"); } /// <summary> /// 检测是否是正确的Url /// </summary> /// <param name="strUrl">要验证的Url</param> /// <returns>判断结果</returns> public static bool IsURL(string strUrl) { return Regex.IsMatch(strUrl, @"^(http|https)\://([a-zA-Z0-9\.\-]+(\:[a-zA-Z0-9\.&%\$\-]+)*@)*((25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])|localhost|([a-zA-Z0-9\-]+\.)*[a-zA-Z0-9\-]+\.(com|edu|gov|int|mil|net|org|biz|arpa|info|name|pro|aero|coop|museum|[a-zA-Z]{1,10}))(\:[0-9]+)*(/($|[a-zA-Z0-9\.\,\?\'\\\+&%\$#\=~_\-]+))*$"); } /// <summary> /// 判断是否为base64字符串 /// </summary> /// <param name="str"></param> /// <returns></returns> public static bool IsBase64String(string str) { //A-Z, a-z, 0-9, +, /, = return Regex.IsMatch(str, @"[A-Za-z0-9\+\/\=]"); } /// <summary> /// 检测是否有Sql危险字符 /// </summary> /// <param name="str">要判断字符串</param> /// <returns>判断结果</returns> public static bool IsSafeSqlString(string str) { return !Regex.IsMatch(str, @"[-|;|,|\/||| | |\}|\{|%|@|\*|!|\']"); } } }