Regular expression for digits and decimals

Hai Friend this might help you.

Regular Expression

 public bool IsNaturalNumber(String strNumber)
    {
        Regex objNotNaturalPattern = new Regex("[^0-9]");
        Regex objNaturalPattern = new Regex("0*[1-9][0-9]*");
        return !objNotNaturalPattern.IsMatch(strNumber) &&
        objNaturalPattern.IsMatch(strNumber);
    }

 public bool IsWholeNumber(String strNumber)
    {
        Regex objNotWholePattern = new Regex("[^0-9]");
        return !objNotWholePattern.IsMatch(strNumber);
    }

 

public bool IsInteger(String strNumber)
    {
        Regex objNotIntPattern = new Regex("[^0-9-]");
        Regex objIntPattern = new Regex("^-[0-9]+$|^[0-9]+$");
        return !objNotIntPattern.IsMatch(strNumber) && objIntPattern.IsMatch(strNumber);
    }

 public bool IsPositiveNumber(String strNumber)
    {
        Regex objNotPositivePattern = new Regex("[^0-9.]");
        Regex objPositivePattern = new Regex("^[.][0-9]+$|[0-9]*[.]*[0-9]+$");
        Regex objTwoDotPattern = new Regex("[0-9]*[.][0-9]*[.][0-9]*");
        return !objNotPositivePattern.IsMatch(strNumber) &&
        objPositivePattern.IsMatch(strNumber) &&
        !objTwoDotPattern.IsMatch(strNumber);
    }

public 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);
    }

  public static bool IsAlphaNumeric(String strToCheck)
    {
        Regex objAlphaNumericPattern = new Regex(@"^[a-zA-Z0-9]*$");
        return !objAlphaNumericPattern.IsMatch(strToCheck);
    }

    public static bool IsAlphaNumericWithSpace(String strToCheck)
    {
        Regex objAlphaNumericSpacePattern = new Regex(@"^[a-zA-Z0-9\s]*$");
        return !objAlphaNumericSpacePattern.IsMatch(strToCheck);
    }

    public static bool IsNumericWithDot(String strToCheck)
    {
        Regex objAlphaNumericPattern = new Regex(@"^[0-9.]*$");
        return !objAlphaNumericPattern.IsMatch(strToCheck);
    }

    public static bool IsNumeric(String strToCheck)
    {
        Regex objNumericPattern = new Regex(@"^[0-9]*$");
        return !objNumericPattern.IsMatch(strToCheck);
    }
    public static bool IsAlphaNumericWithDot(String strToCheck)
    {
        Regex objAlphaNumericPattern = new Regex("[^a-zA-Z0-9.]");
        return !objAlphaNumericPattern.IsMatch(strToCheck);
    }

    public static bool IsAlphaNumericWithDotPeriodSpace(String strToCheck)
    {
        Regex objAlphaNumericPattern = new Regex(@"^[a-zA-Z0-9\s.,]*$");
        return !objAlphaNumericPattern.IsMatch(strToCheck);
    }
 
    public static bool IsAlphaNumericWithDotPeriodSpaceHyphen(String strToCheck)
    {
        Regex objAlphaNumericPattern = new Regex(@"^[a-zA-Z0-9\s.,-]*$");
        return !objAlphaNumericPattern.IsMatch(strToCheck);
    }

    public static bool IsAlphaNumericWithDotPeriodSpaceHyphenSlash(String strToCheck)
    {
        Regex objAlphaNumericPattern = new Regex(@"^[a-zA-Z0-9\s.,-/]*$");
        return !objAlphaNumericPattern.IsMatch(strToCheck);
    }

    public static bool IsAlphaNumericWithSlash(String strToCheck)
    {
        Regex objAlphaNumericPattern = new Regex(@"^[a-zA-Z0-9/]*$");
        return !objAlphaNumericPattern.IsMatch(strToCheck);
    }

    public static bool IsAmount(String strToCheck)
    {
        Regex objAlphaNumericPattern = new Regex(@"^(\d{1,12}|(\d{1,12}\.{1}\d{1,3}){1})$");
        return !objAlphaNumericPattern.IsMatch(strToCheck);
    }

      public static bool IsAmountBECost(String strToCheck)
    {
        Regex objAmountPattern = new Regex(@"^(\d{1,8}|(\d{1,8}\.{1}\d{1,3}){1})$");
        return !objAmountPattern.IsMatch(strToCheck);
    }

  

    public static bool IsValidMail(String strToCheck)
    {
        Regex objEmailPattern = new Regex(@"^[a-z0-9A-Z_\+-.]+(\.[a-z0-9A-Z_\+-.]+)*@[a-z0-9A-Z-]+(\.[a-z0-9A-Z-]+)*\.([a-zA-Z]{2,4})$");
        return !objEmailPattern.IsMatch(strToCheck);
    }