
/* This script and many more are available free online at
The JavaScript Source :: http://javascript.internet.com
Created by: Travis Beckham :: http://www.squidfingers.com | http://www.podlob.com */

// |||||||||||||||||||||||||||||||||||||||||||||||||||||
//
// Coded by Travis Beckham
// http://www.squidfingers.com | http://www.podlob.com
// If want to use this code, feel free to do so, but
// please leave this message intact.
//
// |||||||||||||||||||||||||||||||||||||||||||||||||||||
// --- version date: 11/21/02 --------------------------
// Modified by derrick at reachandteach.com 9/25/07
// returns true if the string is empty
function isEmpty(str){
  return (str == null) || (str.length == 0);
  }
  // returns true if the string is a valid email
  function isEmail(str){
    if(isEmpty(str)) return false;
      var re = /^[^\s()<>@,;:\/]+@\w[\w\.-]+\.[a-z]{2,}$/i
return re.test(str);
}
// returns true if the string only contains characters A-Z or a-z
function isAlpha(str){
  var re = /[^a-zA-Z]/g
    if (re.test(str)) return false;
      return true;
}
// returns true if the string only contains characters 0-9
function isNumeric(str){
var re = /[\D]/g
  if (re.test(str)) return false;
    return true;
    }
    // returns true if the string only contains characters A-Z, a-z or 0-9
    function isAlphaNumeric(str){
      var re = /[^a-zA-Z0-9]/g
if (re.test(str)) return false;
  return true;
  }
  // returns true if the string's length equals "len"
  function isLength(str, len){
    return str.length == len;
    }
    // returns true if the string's length is between "min" and "max"
    function isLengthBetween(str, min, max){
      return (str.length >= min)&&(str.length <= max);
}
// returns true if the string is a US phone number formatted as...
// (000)000-0000, (000) 000-0000, 000-000-0000, 000.000.0000, 000 000 0000, 0000000000
function isPhoneNumber(str){
var re = /^\(?[2-9]\d{2}[\)\.-]?\s?\d{3}[\s\.-]?\d{4}$/
  return re.test(str);
  }
  // returns true if the string is a valid date formatted as...
  // mm dd yyyy, mm/dd/yyyy, mm.dd.yyyy, mm-dd-yyyy
  function isDate(str){
    var re = /^(\d{1,2})[\s\.\/-](\d{1,2})[\s\.\/-](\d{4})$/
      if (!re.test(str)) return false;
var result = str.match(re);
  var m = parseInt(result[1]);
    var d = parseInt(result[2]);
      var y = parseInt(result[3]);
if(m < 1 || m > 12 || y < 1900 || y > 2100) return false;
  if(m == 2){
            var days = ((y % 4) == 0) ? 29 : 28;
      }else if(m == 4 || m == 6 || m == 9 || m == 11){
        var days = 30;
  }else{
            var days = 31;
      }
return (d >= 1 && d <= days);
}
// returns true if "str1" is the same as the "str2"
function isMatch(str1, str2){
  return str1 == str2;
  }
  // returns true if the string contains only whitespace
  // cannot check a password type input for whitespace
  function isWhitespace(str){ // NOT USED IN FORM VALIDATION
    var re = /[\S]/g
      if (re.test(str)) return false;
return true;
}
// removes any whitespace from the string and returns the result
// the value of "replacement" will be used to replace the whitespace (optional)
function stripWhitespace(str, replacement){// NOT USED IN FORM VALIDATION
  if (replacement == null) replacement = '';
    var result = str;
      var re = /\s/g
if(str.search(re) != -1){
    result = str.replace(re, replacement);
      }
return result;
}
// validate the form
function validateForm(f, preCheck){
  var errors = '';
    if(preCheck != null) errors += preCheck;
      var i,e,t,n,v;
for(i=0; i < f.elements.length; i++){
    e = f.elements[i];
    if(e.optional) continue;
    t = e.type;
    n = e.name;
    n1 = e.v;
    if (n1==undefined){continue;}
    v = e.value;
        if(t == 'text' || t == 'password' || t == 'textarea'){
      if(isEmpty(v)){
      errors += n1+' cannot be empty.\n'; continue;
    }
      if(e.isAlpha){
      if(!isAlpha(v)){
        errors += n1+' can only contain characters A-Z a-z.\n'; continue;
        }
      }
    if(e.isNumeric){
            if(!isNumeric(v)){
              errors += n1+' can only contain characters 0-9.\n'; continue;
      }
    }
          if(e.isAlphaNumeric){
          if(!isAlphaNumeric(v)){
            errors += n1+' can only contain characters A-Z a-z 0-9.\n'; continue;
            }
          }
        if(e.isEmail){
        if(!isEmail(v)){
          errors += v+' is not a valid email.\n'; continue;
          }
        }
      if(e.isLength != null){
      var len = e.isLength;
      if(!isLength(v,len)){
        errors += n1+' must contain only '+len+' characters.\n'; continue;
        }
      }
    if(e.isLengthBetween != null){
            var min = e.isLengthBetween[0];
            var max = e.isLengthBetween[1];
            if(!isLengthBetween(v,min,max)){
              errors += n1+' cannot contain less than '+min+' or more than '+max+' characters.\n'; continue;
      }
    }
          if(e.isPhoneNumber){
          if(!isPhoneNumber(v)){
            errors += v+' is not a valid US phone number.\n'; continue;
            }
          }
        if(e.isDate){
        if(!isDate(v)){
          errors += v+' is not a valid date.\n'; continue;
          }
        }
      if(e.isMatch != null){
      if(!isMatch(v, e.isMatch)){
        errors += n1+' does not match.\n'; continue;
        }
      }
  }
      if(t.indexOf('select') != -1){
    if(isEmpty(e.options[e.selectedIndex].value)){
            errors += n1+' needs an option selected.\n'; continue;
          }
      }
  if(t == 'file'){
        if(isEmpty(v)){
        errors += n1+' needs a file to upload.\n'; continue;
      }
  }
    }
      if(errors != '') alert(errors);
return errors == '';
}

/*
The following elements are not validated...

button   type="button"
checkbox type="checkbox"
hidden   type="hidden"
radio    type="radio"
reset    type="reset"
submit   type="submit"

All elements are assumed required and will only be validated for an
empty value or defaultValue unless specified by the following properties.

isEmail = true;          // valid email address
isAlpha = true;          // A-Z a-z characters only
isNumeric = true;        // 0-9 characters only
isAlphaNumeric = true;   // A-Z a-z 0-9 characters only
isLength = number;       // must be exact length
isLengthBetween = array; // [lowNumber, highNumber] must be between lowNumber and highNumber
isPhoneNumber = true;    // valid US phone number. See "isPhoneNumber()" comments for the formatting rules
isDate = true;           // valid date. See "isDate()" comments for the formatting rules
isMatch = string;        // must match string
optional = true;         // element will not be validated
*/
