A small, quick, and simple method of verify fields in a form.

Readme.txt

Name: restrictInput
Signature: restrictInput(string type, event keypress);
Description: Restricts input to fields to specified values

Usage: $("#myfieldID").keydown(function(e)){
          restrictInput("alpha",e);
       };

Types:
  alphanumeric - All letters and numbers
  digit - Numbers only
  letters - Letters only, to include upper and lower case

================================================================================

Name: autoVerify
Signature:bool autoVerify(string classname,bool highlightFields, bool showErrors)
Description: Performs automatic verification of specified fields

Usage: if(autoVerify("myclass", true, false)){
         alert("Fields are valid!");
       }else{
         alert("Fields are not valid!");
       }

Details:  In order for the auto verify to work properly the fields are required to have
	specific HTML attributes.  These attributes and their purposes are defined below.

Required?	Attribute			Purpose
------------------------------------------------------------------------------------------------------------------------
    Y       |     id        |   Required field, allows highlighting and field identification
    Y       |   valid-name  |   Gives the field a user-friendly name for display purposes
    N       |   valid-type  |   Specifies the type of validation to be performed (string, number, money, or email [Default: string])
    N       |valid-required |   Specifies whether the field is required or not
    N       |   valid-min   |   Specifies the minimum acceptable value.  (For number or money this is a defined amount, for string it is the string length)
    N       |   valid-max   |   Specifies the maximum acceptable value.  (For number or money this is a defined amount, for string it is the string length)

===============================================================================

Name: getAutoVerifyObj
Signature: getAutoVerifyObj(string className)
Description: Generates objects for use by the verifyFields function from CSS class name.  See the table under autoVerify for further details.

Usage: var fields = getAutoVerifyObj("myclassname");
       if(verifyFields(fields,true,false)){
         alert("Fields are valid!");
       }else{
         alert("Fields are not valid!");
       }

===============================================================================

Name: verifyFields
Signature:bool verifyFields(obj[] fields, bool highlightFields, bool showError)
Description: Performs validation on a collection of field objects

Usage: var field = new { id: "myfield", name:"somefield", type: "string", required: true};
       var fields[] = {field};
       if(verifyFields(fields,true,false)){
         alert("Fields are valid!");
       }else{
         alert("Fields are not valid!");
       }

Details: Performs manual validation on supplied fields.   Best to use autoVerify rather than using this, or use the getAutoVerifyObj in conjuction

validation.js

function formatMoney(className) {
    if (className === undefined) {
        className = "money";
    }

    var elements = $("." + className);

    var numString = elements.text();
    var numFloat = parseFloat(numString);

    //Ensure that decimal places only go to 2
    var digitMatch = ('' + numString).match(/(?:\.(\d+))?(?:[eE]([+-]?\d+))?$/);
    if (match) {
        var digitPlacement = Math.max(0, (match[1] ? match[1].length : 0) - (match[2] ? +match[2] : 0));
        if (digitPlacement > 2) {
            elements.text(numFloat.toFixed(2));
        }
    }

    elements.prepend("$");
}

function cleanNumber(mystring) {
    if (mystring === undefined) {
        return undefined;
    }
    var cleanedNumber;
    cleanedNumber = mystring.replace(/[^0-9\.\-]/g, '');
    return cleanedNumber;
}

function getAutoVerifyObj(className) {
    var objArr = Array();

    $("." + className).each(function (i, obj) {
        var validType = $(this).attr('valid-type');
        var validName = $(this).attr('valid-name');
        var id = $(this).attr('id');
        var required = $(this).attr('valid-required');
        var min = $(this).attr('valid-min');
        var max = $(this).attr('valid-max');

        var obj = { id: id, name: validName };

        if (isDefined(validType)) {
            obj.type = validType;
        }

        if (isDefined(required)) {
            obj.required = required;
        }

        if (isDefined(min)) {
            obj.min = min;
        }

        if (isDefined(max)) {
            obj.max = max;
        }

        objArr.push(obj);
    });

    return objArr;
}

function restrictInput(type,event) {
    if (type === undefined) {
        type = "alphanumeric";
    }

    var digits = [48, 49, 50, 51, 52, 53, 54, 55, 56, 57];
    var numpad = [96, 97, 98, 99, 100, 101, 102, 103, 104, 105];
    var letters = [65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90];
    var navigation = [35, 36, 37, 38, 39, 40];
    var control = [8, 9, 13, 16, 17, 18, 19, 20, 27, 33, 34, 45, 46];
    var special = [106,107,109,110,111,186,187,188,189,190,191,192,219,220,221,222];

    if (type == "alphanumeric") {
        if (($.inArray(event.keyCode, digits) !== -1) || 
            ($.inArray(event.keyCode, letters) !== -1) || 
            ($.inArray(event.keyCode, control) !== -1) || 
            ($.inArray(event.keyCode, navigation) !== -1) || 
            ($.inArray(event.keyCode, numpad) !== -1)) { 
            return;
        } else {
            event.preventDefault();
        }
    }

    if (type == "digit") {
        if (($.inArray(event.keyCode, digits) !== -1) || //Check if digit
            ($.inArray(event.keyCode, navigation) !== -1) ||
            ($.inArray(event.keyCode, control) !== -1) ||
            ($.inArray(event.keyCode, numpad) !== -1)) { //Check if numpad digit
            return;
        } else {
            event.preventDefault();
        }
    }

    if (type == "letters") {
        if (($.inArray(event.keyCode, letters) !== -1) ||
            ($.inArray(event.keyCode, navigation) !== -1) ||
            ($.inArray(event.keyCode, control) !== -1)
            ) { //Check if letter
            return;
        } else {
            event.preventDefault();
        }
    }

    return;
}

function autoVerify(className,highlightFields,showError){
    if(highlightFields === undefined){
        highlightFields = false;
    }

    if(showError === undefined){
        showError = false;
    }

    var objArr = Array();

    $("."+className).each(function(i, obj) {
        var validType = $(this).attr('valid-type');
        var validName = $(this).attr('valid-name');
        var id = $(this).attr('id');
        var required = $(this).attr('valid-required');
        var min = $(this).attr('valid-min');
        var max = $(this).attr('valid-max');
                
        var obj = {id:id,name:validName};
                
        if(isDefined(validType)){
            obj.type = validType;
        }
                
        if(isDefined(required)){
            obj.required = required;
        }
                
        if(isDefined(min)){
            obj.min = min;
        }
                
        if(isDefined(max)){
            obj.max = max;
        }
                
        objArr.push(obj);
    });

    return verifyFields(objArr,highlightFields,showError);
}

function isDefined(object){
    if(typeof(object)!== typeof(undefined) && object !==false && object !== undefined){
        return true;
    }
    return false;
}

function validateEmail(emailField) {
    var reg = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;

    if (reg.test(emailField) == false) {
        return false;
    }

    return true;

}

function verifyFields(fields, highlightFields, showError) {

    if (showError === undefined) {
        showError = false;
    }

    if (highlightFields === undefined) {
        highlightFields = false;
    }

    var errorCount = 0;
    var ValidationErrors = Array();
    var ValidationFields = Array();
    var ValidationReason = Array();

    fields.forEach(function (field) {
        if (!("id" in field)) {
            alert("Field ID not defined!");
            return;
        }

        if (!("name" in field)) {
            alert("Field name not defined!");
            return;
        }

        var fieldType = field["type"];
        var fieldId = field["id"];
        var fieldName = field["name"];
        var fieldValue = $("#" + fieldId).val();

        //Remove old css classes
        $("#" + fieldId).removeClass('invalidfield');

        //Different methods between checking empty inputs and selects
        if (fieldType != "select") {
            if ("required" in field) {
                if (new Boolean(field["required"])) {
                    if ($("#" + fieldId).val() == "") {
                        ValidationFields[errorCount] = fieldId;
                        ValidationErrors[errorCount] = fieldName;
                        ValidationReason[errorCount] = "is required.";
                        errorCount += 1;
                    }
                }
            }
        } else {
            if ("required" in field) {
                if (new Boolean(field["required"])) {
                    if ($("#" + fieldId + " :selected").val() == "") {
                        ValidationFields[errorCount] = fieldId;
                        ValidationErrors[errorCount] = fieldName;
                        ValidationReason[errorCount] = "is required.";
                        errorCount += 1;
                    }
                }
            }
        }

        switch (fieldType) {
            case "email":

                if (!validateEmail(fieldValue)) {
                    ValidationFields[errorCount] = fieldId;
                    ValidationErrors[errorCount] = fieldName;
                    ValidationReason[errorCount] = "is not a valid email.";
                    errorCount += 1;
                }
                break;

            case "number":
            case "money":
                if (!jQuery.isNumeric(cleanNumber(fieldValue))){
                    ValidationFields[errorCount] = fieldId;
                    ValidationErrors[errorCount] = fieldName;
                    ValidationReason[errorCount] = "is not a valid number.";
                    errorCount += 1;
                }

                if ("min" in field) {
                    var min = field["min"];
                    if (parseFloat(fieldValue) < parseFloat(min)) {
                        ValidationFields[errorCount] = fieldId;
                        ValidationErrors[errorCount] = fieldName;
                        ValidationReason[errorCount] = "is below the minimum value.";
                        errorCount += 1;
                    }
                }

                if ("max" in field) {
                    var max = field["max"];
                    if (parseFloat(fieldValue) > parseFloat(max)) {
                        ValidationFields[errorCount] = fieldId;
                        ValidationErrors[errorCount] = fieldName;
                        ValidationReason[errorCount] = "is above the maximum value.";
                        errorCount += 1;
                    }
                }
                break;

                //String
            default:
                if ("min" in field) {
                    var min = field["min"];
                    if (fieldValue.length < parseFloat(min)) {
                        ValidationFields[errorCount] = fieldId;
                        ValidationErrors[errorCount] = fieldName;
                        ValidationReason[errorCount] = "is below the minimum value.";
                        errorCount += 1;
                    }
                }

                if ("max" in field) {
                    var max = field["max"];
                    if (fieldValue.length > parseFloat(max)) {
                        ValidationFields[errorCount] = fieldId;
                        ValidationErrors[errorCount] = fieldName;
                        ValidationReason[errorCount] = "is above the maximum value.";
                        errorCount += 1;
                    }
                }
                break;
        }
    });

    //If there were any errors do the field highlighting and error display here
    if (errorCount > 0) {
        if (new Boolean(highlightFields)) {
            for (var i = 0, len = ValidationErrors.length; i < len; i++) {
                $("#"+ValidationFields[i]).addClass('invalidfield');
            }
        }

        if (new Boolean(showError)) {
            var errorMessage = "Please enter valid input in the following fields:<br/><ul>";

            //For loop crafts error message
            for (var i = 0, len = ValidationErrors.length; i < len; i++) {
                errorMessage = errorMessage + "<li>"+ValidationErrors[i]+ " " + ValidationReason[i] + "</li>";
            }
            errorMessage = errorMessage + "</ul>";

            //Dependant on 
            createErrorDialog(errorMessage);
        }

        return false;
    }
    return true;
}

function createErrorDialog(errorMessage){
  var dialogHtml = "<div id=\"error-dialog\" title=\"Error Message\"><div class=\"dialog-message\"></div></div>";
  
  $(document.body).append(dialogHtml);

	$("#error-dialog").dialog({
  	modal: true,
    draggable: false,
    resizable: true,
    position: ['center','top'],
    show: 'blind',
    hide: 'blind',
    width: 400,
    buttons: {
      "Close": function(){
        destroyErrorDialog();
      }
    }
  });
  $("#error-dialog .dialog-message").html(errorMessage);
  $("#error-dialog").dialog("open");
}

function destroyErrorDialog(){
	$("#error-dialog").remove();
}