C# 判断一字符串是否为合法数字，正则表达式

/// <summary>

/// 判断一个字符串是否为合法整数(不限制长度)

/// </summary>

/// <param name="s">字符串</param>

/// <returns></returns>

public static bool IsInteger(string s)

{

string pattern = @"^\d*$";

return Regex.IsMatch(s,pattern);

}

/**//// <summary>

/// 判断一个字符串是否为合法数字(0-32整数)

/// </summary>

/// <param name="s">字符串</param>

/// <returns></returns>

public static bool IsNumber(string s)

{

return IsNumber(s,32,0);

}

/**//// <summary>

/// 判断一个字符串是否为合法数字(指定整数位数和小数位数)

/// </summary>

/// <param name="s">字符串</param>

/// <param name="precision">整数位数</param>

/// <param name="scale">小数位数</param>

/// <returns></returns>

public static bool IsNumber(string s,int precision,int scale)

{

if((precision == 0)&&(scale == 0))

{

return false;

}

string pattern = @"(^\d{1,"+precision+"}";

if(scale>0)

{

pattern += @"\.\d{0,"+scale+"}$)|"+pattern;

}

pattern += "$)";

return Regex.IsMatch(s,pattern);

}