JavaScript RegEx Validation - Regular Expressions

By Devil Scorpio

Common validation and formating javascript functions using Regular Expressions

Problem Description

Simple and reusable, validation and formating functions using Regular Expressions.

Solution Description

The solution is a javascript file, where common and resuable validation methods used are listed and ready to use. The validation's and formating are done entirely using Regular Expressions, to make the solution simple and robust.


Code Snippet

function validateCurrency( strValue)  {
/************************************************
DESCRIPTION: Validates that a string contains a
  valid currency format.
  
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.
*************************************************/
  var objRegExp = /(^\$\d{1,3}(,\d{3})*\.\d{2}$)|(^\(\$\d{1,3}(,\d{3})*\.\d{2}\)$)/;

  return objRegExp.test( strValue );
}

function validateTime ( strValue ) {
/************************************************
DESCRIPTION: Validates that a string contains a
  valid 12 hour time format. Seconds are optional.
  
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.

REMARKS: Returns True for time formats such as:
  HH:MM or HH:MM:SS or HH:MM:SS.mmm (where the
  .mmm is milliseconds as used in SQL Server
  datetime datatype.  Also, the .mmm portion will
  accept 1 to 3 digits after the period)
*************************************************/
  var objRegExp = /^([1-9]|1[0-2]):[0-5]\d(:[0-5]\d(\.\d{1,3})?)?$/;

  return objRegExp.test( strValue );

}

function validateState (strValue ) {
/************************************************
DESCRIPTION: Validates that a string contains a
  valid state abbreviation.
  
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.
*************************************************/

var objRegExp = /^(AK|AL|AR|AZ|CA|CO|CT|DC|DE|FL|GA|HI|IA|ID|IL|IN|KS|KY|LA|MA|MD|ME|MI|MN|MO|MS|MT|NB|NC|ND|NH|NJ|NM|NV|NY|OH|
OK|OR|PA|RI|SC|SD|TN|TX|UT|VA|VT|WA|WI|WV|WY)$/i;

  return objRegExp.test(strValue);
}

function validateSSN( strValue ) {
/************************************************
DESCRIPTION: Validates that a string contains a
  valid social security number.
  
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.
*************************************************/
var objRegExp  = /^\d{3}\-\d{2}\-\d{4}$/;

  //check for valid SSN
  return objRegExp.test(strValue);

}


function validateEmail( strValue) {
/************************************************
DESCRIPTION: Validates that a string contains a
  valid email pattern.
  
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.
  
REMARKS: Accounts for email with country appended
  does not validate that email contains valid URL
  type (.com, .gov, etc.) and optionally,
  a valid country suffix.  Since email has many
  forms this expression only tests for near valid
  address.  Some additional validation may be
  required.
*************************************************/
var objRegExp  = /^[a-z0-9]([a-z0-9_\-\.]*)@([a-z0-9_\-\.]*)(\.[a-z]{2,3}(\.[a-z]{2}){0,2})$/i;
  //check for valid email
  return objRegExp.test(strValue);
}

function validateUSPhone( strValue ) {
/************************************************
DESCRIPTION: Validates that a string contains valid
  US phone pattern.
  Ex. (999) 999-9999 or (999)999-9999
  
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.
*************************************************/
  var objRegExp  = /^\([1-9]\d{2}\)\s?\d{3}\-\d{4}$/;

  //check for valid us phone with or without space between
  //area code
  return objRegExp.test(strValue);
}

function  validateNumeric( strValue ) {
/******************************************************************************
DESCRIPTION: Validates that a string contains only valid numbers.

PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.
******************************************************************************/
  var objRegExp  =  /(^-?\d\d*\.\d*$)|(^-?\d\d*$)|(^-?\.\d\d*$)/;

  //check for numeric characters
  return objRegExp.test(strValue);
}

function validateInteger( strValue ) {
/************************************************
DESCRIPTION: Validates that a string contains only
    valid integer number.
    
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.
******************************************************************************/
  var objRegExp  = /(^-?\d\d*$)/;

  //check for integer characters
  return objRegExp.test(strValue);
}

function validateNotEmpty( strValue ) {
/************************************************
DESCRIPTION: Validates that a string is not all
  blank (whitespace) characters.
    
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.
*************************************************/
   var strTemp = strValue;
   strTemp = trimAll(strTemp);
   if(strTemp.length > 0){
     return true;
   }  
   return false;
}

function validateUSZip( strValue ) {
/************************************************
DESCRIPTION: Validates that a string a United
  States zip code in 5 digit format or zip+4
  format. 99999 or 99999-9999
    
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.

*************************************************/
var objRegExp  = /(^\d{5}$)|(^\d{5}-\d{4}$)/;

  //check for valid US Zipcode
  return objRegExp.test(strValue);
}

function validateUSDate( strValue ) {
/************************************************
DESCRIPTION: Validates that a string contains only
    valid dates with 2 digit month, 2 digit day,
    4 digit year. Date separator can be ., -, or /.
    Uses combination of regular expressions and
    string parsing to validate date.
    Ex. mm/dd/yyyy or mm-dd-yyyy or mm.dd.yyyy
    
PARAMETERS:
   strValue - String to be tested for validity
  
RETURNS:
   True if valid, otherwise false.
  
REMARKS:
   Avoids some of the limitations of the Date.parse()
   method such as the date separator character.
*************************************************/
  var objRegExp = /^\d{1,2}(\-|\/|\.)\d{1,2}\1\d{4}$/

  //check to see if in correct format
  if(!objRegExp.test(strValue))
    return false; //doesn't match pattern, bad date
  else{
    var arrayDate = strValue.split(RegExp.$1); //split date into month, day, year
var intDay = parseInt(arrayDate[1],10);
var intYear = parseInt(arrayDate[2],10);
    var intMonth = parseInt(arrayDate[0],10);

//check for valid month
if(intMonth > 12 || intMonth < 1) {
return false;
}

    //create a lookup for months not equal to Feb.
    var arrayLookup = { '01' : 31,'03' : 31, '04' : 30,'05' : 31,'06' : 30,'07' : 31,
                        '08' : 31,'09' : 30,'10' : 31,'11' : 30,'12' : 31}
  
    //check if month value and day value agree
    if(arrayLookup[arrayDate[0]] != null) {
      if(intDay <= arrayLookup[arrayDate[0]] && intDay != 0)
        return true; //found in lookup table, good date
    }

    //check for February
var booLeapYear = (intYear % 4 == 0 && (intYear % 100 != 0 || intYear % 400 == 0));
    if( ((booLeapYear && intDay <= 29) || (!booLeapYear && intDay <=28)) && intDay !=0)
      return true; //Feb. had valid number of days
  }
  return false; //any other values, bad date
}

function validateValue( strValue, strMatchPattern ) {
/************************************************
DESCRIPTION: Validates that a string a matches
  a valid regular expression value.
    
PARAMETERS:
   strValue - String to be tested for validity
   strMatchPattern - String containing a valid
      regular expression match pattern.
      
RETURNS:
   True if valid, otherwise false.
*************************************************/
var objRegExp = new RegExp( strMatchPattern);

//check if string matches pattern
return objRegExp.test(strValue);
}


function rightTrim( strValue ) {
/************************************************
DESCRIPTION: Trims trailing whitespace chars.
    
PARAMETERS:
   strValue - String to be trimmed.  
      
RETURNS:
   Source string with right whitespaces removed.
*************************************************/
var objRegExp = /^([\w\W]*)(\b\s*)$/;

      if(objRegExp.test(strValue)) {
       //remove trailing a whitespace characters
       strValue = strValue.replace(objRegExp, '$1');
    }
  return strValue;
}

function leftTrim( strValue ) {
/************************************************
DESCRIPTION: Trims leading whitespace chars.
    
PARAMETERS:
   strValue - String to be trimmed
  
RETURNS:
   Source string with left whitespaces removed.
*************************************************/
var objRegExp = /^(\s*)(\b[\w\W]*)$/;

      if(objRegExp.test(strValue)) {
       //remove leading a whitespace characters
       strValue = strValue.replace(objRegExp, '$2');
    }
  return strValue;
}

function trimAll( strValue ) {
/************************************************
DESCRIPTION: Removes leading and trailing spaces.

PARAMETERS: Source string from which spaces will
  be removed;

RETURNS: Source string with whitespaces removed.
*************************************************/
var objRegExp = /^(\s*)$/;

    //check for all spaces
    if(objRegExp.test(strValue)) {
       strValue = strValue.replace(objRegExp, '');
       if( strValue.length == 0)
          return strValue;
    }
    
   //check for leading & trailing spaces
   objRegExp = /^(\s*)([\W\w]*)(\b\s*$)/;
   if(objRegExp.test(strValue)) {
       //remove leading and trailing whitespace characters
       strValue = strValue.replace(objRegExp, '$2');
    }
  return strValue;
}

function removeCurrency( strValue ) {
/************************************************
DESCRIPTION: Removes currency formatting from
  source string.
  
PARAMETERS:
  strValue - Source string from which currency formatting
     will be removed;

RETURNS: Source string with commas removed.
*************************************************/
  var objRegExp = /\(/;
  var strMinus = '';

  //check if negative
  if(objRegExp.test(strValue)){
    strMinus = '-';
  }
  
  objRegExp = /\)|\(|[,]/g;
  strValue = strValue.replace(objRegExp,'');
  if(strValue.indexOf('$') >= 0){
    strValue = strValue.substring(1, strValue.length);
  }
  return strMinus + strValue;
}

function addCurrency( strValue ) {
/************************************************
DESCRIPTION: Formats a number as currency.

PARAMETERS:
  strValue - Source string to be formatted

REMARKS: Assumes number passed is a valid
  numeric value in the rounded to 2 decimal
  places.  If not, returns original value.
*************************************************/
  var objRegExp = /-?[0-9]+\.[0-9]{2}$/;
  
    if( objRegExp.test(strValue)) {
      objRegExp.compile('^-');
      strValue = addCommas(strValue);
      if (objRegExp.test(strValue)){
        strValue = '($' + strValue.replace(objRegExp,'') + ')';
      }
      else {
        strValue = '$' + strValue;
      }
      return  strValue;
    }
    else
      return strValue;
}

function removeCommas( strValue ) {
/************************************************
DESCRIPTION: Removes commas from source string.

PARAMETERS:
  strValue - Source string from which commas will
    be removed;

RETURNS: Source string with commas removed.
*************************************************/
  var objRegExp = /,/g; //search for commas globally

  //replace all matches with empty strings
  return strValue.replace(objRegExp,'');
}

function addCommas( strValue ) {
/************************************************
DESCRIPTION: Inserts commas into numeric string.

PARAMETERS:
  strValue - source string containing commas.
  
RETURNS: String modified with comma grouping if
  source was all numeric, otherwise source is
  returned.
  
REMARKS: Used with integers or numbers with
  2 or less decimal places.
*************************************************/
  var objRegExp  = new RegExp('(-?[0-9]+)([0-9]{3})');

    //check for match to search criteria
    while(objRegExp.test(strValue)) {
       //replace original string with first group match,
       //a comma, then second group match
       strValue = strValue.replace(objRegExp, '$1,$2');
    }
  return strValue;
}

function removeCharacters( strValue, strMatchPattern ) {
/************************************************
DESCRIPTION: Removes characters from a source string
  based upon matches of the supplied pattern.

PARAMETERS:
  strValue - source string containing number.
  
RETURNS: String modified with characters
  matching search pattern removed
  
USAGE:  strNoSpaces = removeCharacters( ' sfdf  dfd',
                                '\s*')
*************************************************/
var objRegExp =  new RegExp( strMatchPattern, 'gi' );

//replace passed pattern matches with blanks
  return strValue.replace(objRegExp,'');
}

JavaScript RegEx Validation - Regular Expressions  (1461 Views)