验证是否是正整数，是否是mail，是否是正确的身份证

/// <summary>
/// 通用验证类
/// </summary>
class DataValidate
{
/// <summary>
/// 验证正整数
/// </summary>
/// <param name="txt"></param>
/// <returns></returns>
public static bool IsInteger(string txt)
{
Regex objReg = new Regex(@"^[1-9]\d*$");
return objReg.IsMatch(txt);
}
/// <summary>
/// 验证是否是Email
/// </summary>
/// <param name="txt"></param>
/// <returns></returns>
public static bool IsEmail(string txt)
{
Regex objReg = new Regex(@"\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*");
return objReg.IsMatch(txt);
}
/// <summary>
/// 验证身份证
/// </summary>
/// <param name="txt"></param>
/// <returns></returns>
public static bool IsIdentityCard(string txt)
{
Regex objReg = new Regex(@"^(\d{15}$|^\d{18}$|^\d{17}(\d|X|x))$");
return objReg.IsMatch(txt);
}