Summary One weakness of the .NET validators is that they take an all or nothing approach to validation. If you have a validators on the page and you invoke validation every validator will be evaluated if it is enabled no matter which button was clicked. This posed a problem for me while recently developing a new product. The requirement was that there should always be a login element in the upper left hand corner which has required and regular expression field validators. Everything was fine until I add a registration page which also had validators. I obviously needed some separation between the two, because when the user clicked the "Login" button the webform was firing the "Registration" field validators. Essentially, what I did to get around this is modified the WebUIValidation.js file and created a derived page of the System.Web.UI.Page class in which I overrided the Page_Load and Validate methods, as well as added a ValidatorAssignments property. Modifying both the client (.js) file and the server files ensures that the validation will function as desired both on the client and server. WebUIValidation.js Modifications The modification to this file are done in the Page_ClientValidate function.

var Page_InitValidators; // Stores all the original validators
function Page_ClientValidate() {
    var i;
    // Page_ValidatorAssignments gets rendered in the derived Page Class, if we have the variable on the page
    // And it is set to true then process.
    if( typeof(Page_ValidatorAssignments) != 'undefined' && Page_ValidatorAssignments == true )
    {
		// Store all the validators if not already done.
		if( Page_InitValidators == null )
			Page_InitValidators = Page_Validators;
		

		// Each validator assignment will render a client side array.  We grab that value here
		// And assign it to the Page_Validators variable.
		Page_Validators = eval(event.srcElement.id + "Validators");
		

		//  Loop through are new validators and evaluate them (cast them to DOM objects)
		for(i = 0; i < Page_Validators.length; i++ )
		{
			Page_Validators[i] = eval(Page_Validators[i]);
		}
		

		// Loop through all the InitValidators and enable/disable depending on if they are
		// Assinged to the current button or not.
		for(i = 0; i < Page_InitValidators.length; i++ )
		{
			// InArray returns -1 if the passed element is not in array, otherwise returns index of element
			if( InArray(Page_Validators, Page_InitValidators[i].id, "id") == -1 )
			{
				Page_InitValidators[i].isvalid = true;
				ValidatorEnable(Page_InitValidators[i], false);
				ValidatorUpdateDisplay(Page_InitValidators[i]);
			}
			else
			{
				ValidatorEnable(Page_InitValidators[i], true);
			}
		}
		

	}
    for (i = 0; i < Page_Validators.length; i++) {
		ValidatorValidate(Page_Validators[i]);
    }
    ValidatorUpdateIsValid();
    ValidationSummaryOnSubmit();
    Page_BlockSubmit = !Page_IsValid;
    return Page_IsValid;
}


// Returns the index of the "value" in the given array.
// Returns -1 if not found in array.
function InArray(array, value, attribute)
{
	if( attribute != null )
		attribute += ".";
		

	for(var i = 0; i < array.length;i++)
	{
		if( eval('array[i].' + attribute + 'toString().toLowerCase()') == value.toString().toLowerCase() )
			return i;
	}
	return -1;
}

System.Web.UI.Page Derived Class 1. Deriving from a .NET Class - It's simple. Just as follows.

public class WebPage : System.Web.UI.Page

2. ValidatorAssignments Property - This will store the validator assignments in a System.Collections.Specialized NameValueCollection object.

public NameValueCollection ValidatorAssignments
{
	get
	{
		return validatorAssignments;
	}
	set
	{
		validatorAssignments = value;
	}
}
private NameValueCollection validatorAssignments = null;

You will need to modify the constructor of the derived WebPage class to instantiate the new property.

		
public WebPage()
{
	validatorAssignments = new NameValueCollection();
}

3. Page_Load Override - We will override this method to render the client side variable needed to trigger validator assignments and the arrays that contain the button specific validator assignments.

private void Page_Load( object sender, System.EventArgs e )
{
	if( this.validatorAssignments != null && this.validatorAssignments.HasKeys() )
	{
		StringBuilder sb = new StringBuilder();
		sb.Append("<script >");
		sb.Append(Environment.NewLine);
		sb.Append("Page_ValidatorAssignments = true;");
		sb.Append(Environment.NewLine);
		for( int i = 0; i < this.validatorAssignments.Count; i++ )
		{
			if( this.validatorAssignments.Keys[i].ToString() != string.Empty && this.validatorAssignments[i].ToString() != string.Empty )
			{
				sb.AppendFormat(" var {0}Validators = new Array(", this.validatorAssignments.Keys[i].ToString());
				string[] keys = this.validatorAssignments[i].Split(",".ToCharArray());
				for( int k = 0; k < keys.Length; k++ )
				{
					sb.AppendFormat("'document.all[\"{0}\"]'", keys[k].Trim());
					if( k != keys.Length - 1 )
						sb.Append(",");
				}
				sb.Append(");");
				sb.Append(Environment.NewLine);

			}
		}
		sb.Append(Environment.NewLine);
		sb.Append("</script>");
		Page.RegisterClientScriptBlock("ValidatorAssignments", sb.ToString());
	}
}

4. Validate Override - We will first check if we have validator assignments, grab the button that was clicked from the request object and then disable all validators that are not assigned to that button.

public override void Validate()
{
	for( int i = 0; i < this.validatorAssignments.Count; i++ )
	{
		if( Request.Form[this.validatorAssignments.Keys[i].Replace("_", ":")] != null )
		{
			ArrayList assignedValidators = new ArrayList(this.validatorAssignments[i].Split(",".ToCharArray()));
			for( int k = 0; k < this.Validators.Count; k++ )
			{
				BaseValidator bv = (BaseValidator)this.Validators[k];
				if(!assignedValidators.Contains(bv.ClientID))
				{
					bv.Enabled = false;
				}
			}
			break;
		}
	}

	base.Validate();
	
}

Assigning Validators Validators are assigned at the page level in the Page_Init function. You page must be derived from your new WebPage class. You assign validators to buttons with the ValidatorAssignment.Add method. The first parameter is the button name and the second parameter is a comma delimited list of the validator ID you want to assign to the button.

override protected void OnInit(EventArgs e)
{
	InitializeComponent();
	this.ValidatorAssignments.Add("btnActivate", "rfvEmail,revEmail,rfvActivationCode");
	base.OnInit(e);
}

To assign a ValidatorAssignments from a UserControl, use the following method. This will modify the Parent page's ValidatorAssignments property (the Parent page must be derived from your new WebPage class)

((Test.WebControls.WebPage)this.Parent.Page).ValidatorAssignments.Add("{0}_btnLogin".Replace("{0}", this.ID), "{0}_rfvEmail,{0}_rfvPassword,{0}_revEmail".Replace("{0}", this.ID));

That's all there is to it. If you have any questions, find bugs or have any comments please post here. ============================= Complete Code ============================= WebUIValidation.js

var Page_ValidationVer = "125";
var Page_IsValid = true;
var Page_BlockSubmit = false;
function ValidatorUpdateDisplay(val) {
    if (typeof(val.display) == "string") {    
        if (val.display == "None") {
            return;
        }
        if (val.display == "Dynamic") {
            val.style.display = val.isvalid ? "none" : "inline";
            return;
        }
    }
    val.style.visibility = val.isvalid ? "hidden" : "visible";
}
function ValidatorUpdateIsValid() {
    var i;
    for (i = 0; i < Page_Validators.length; i++) {
        if (!Page_Validators[i].isvalid) {
            Page_IsValid = false;
            return;
        }
   }
   Page_IsValid = true;
}
function ValidatorHookupControlID(controlID, val) {
    if (typeof(controlID) != "string") {
        return;
    }
    var ctrl = document.all[controlID];
    if (typeof(ctrl) != "undefined") {
        ValidatorHookupControl(ctrl, val);
    }
    else {
        val.isvalid = true;
        val.enabled = false;
    }
}
function ValidatorHookupControl(control, val) {
    if (typeof(control.tagName) == "undefined" && typeof(control.length) == "number") {
        var i;
        for (i = 0; i < control.length; i++) {
            var inner = control[i];
            if (typeof(inner.value) == "string") {
                ValidatorHookupControl(inner, val);
            } 
        }
        return;
    }
    else if (control.tagName != "INPUT" && control.tagName != "TEXTAREA" && control.tagName != "SELECT") {
        var i;
        for (i = 0; i < control.children.length; i++) {
            ValidatorHookupControl(control.children[i], val);
        }
        return;
    }
    else {
        if (typeof(control.Validators) == "undefined") {
            control.Validators = new Array;
            var ev;
            if (control.type == "radio") {
                ev = control.onclick;
            } else {
                ev = control.onchange;
            }
            if (typeof(ev) == "function" ) {            
                ev = ev.toString();
                ev = ev.substring(ev.indexOf("{") + 1, ev.lastIndexOf("}"));
            }
            else {
                ev = "";
            }
            var func = new Function("ValidatorOnChange(); " + ev);
            if (control.type == "radio") {
                control.onclick = func;
            } else {            
                control.onchange = func;
            }
        }
        control.Validators[control.Validators.length] = val;
    }    
}
function ValidatorGetValue(id) {
    var control;
    control = document.all[id];
    if (typeof(control.value) == "string") {
        return control.value;
    }
    if (typeof(control.tagName) == "undefined" && typeof(control.length) == "number") {
        var j;
        for (j=0; j < control.length; j++) {
            var inner = control[j];
            if (typeof(inner.value) == "string" && (inner.type != "radio" || inner.status == true)) {
                return inner.value;
            }
        }
    }
    else {
        return ValidatorGetValueRecursive(control);
    }
    return "";
}
function ValidatorGetValueRecursive(control)
{
    if (typeof(control.value) == "string" && (control.type != "radio" || control.status == true)) {
        return control.value;
    }
    var i, val;
    for (i = 0; i0 ? m[2] : "0") + "." + m[4];
        num = parseFloat(cleanInput);
        return (isNaN(num) ? null : num);            
    } 
    else if (dataType == "Currency") {
        exp = new RegExp("^\\s*([-\\+])?(((\\d+)\\" + val.groupchar + ")*)(\\d+)"
                        + ((val.digits > 0) ? "(\\" + val.decimalchar + "(\\d{1," + val.digits + "}))?" : "")
                        + "\\s*$");
        m = op.match(exp);
        if (m == null)
            return null;
        var intermed = m[2] + m[5] ;
        cleanInput = m[1] + intermed.replace(new RegExp("(\\" + val.groupchar + ")", "g"), "") + ((val.digits > 0) ? "." + m[7] : 0);
        num = parseFloat(cleanInput);
        return (isNaN(num) ? null : num);            
    }
    else if (dataType == "Date") {
        var yearFirstExp = new RegExp("^\\s*((\\d{4})|(\\d{2}))([-./])(\\d{1,2})\\4(\\d{1,2})\\s*$");
        m = op.match(yearFirstExp);
        var day, month, year;
        if (m != null && (m[2].length == 4 || val.dateorder == "ymd")) {
            day = m[6];
            month = m[5];
            year = (m[2].length == 4) ? m[2] : GetFullYear(parseInt(m[3], 10))
        }
        else {
            if (val.dateorder == "ymd"){
                return null;		
            }						
            var yearLastExp = new RegExp("^\\s*(\\d{1,2})([-./])(\\d{1,2})\\2((\\d{4})|(\\d{2}))\\s*$");
            m = op.match(yearLastExp);
            if (m == null) {
                return null;
            }
            if (val.dateorder == "mdy") {
                day = m[3];
                month = m[1];
            }
            else {
                day = m[1];
                month = m[3];
            }
            year = (m[5].length == 4) ? m[5] : GetFullYear(parseInt(m[6], 10))
        }
        month -= 1;
        var date = new Date(year, month, day);
        return (typeof(date) == "object" && year == date.getFullYear() && month == date.getMonth() && day == date.getDate()) ? date.valueOf() : null;
    }
    else {
        return op.toString();
    }
}
function ValidatorCompare(operand1, operand2, operator, val) {
    var dataType = val.type;
    var op1, op2;
    if ((op1 = ValidatorConvert(operand1, dataType, val)) == null)
        return false;    
    if (operator == "DataTypeCheck")
        return true;
    if ((op2 = ValidatorConvert(operand2, dataType, val)) == null)
        return true;
    switch (operator) {
        case "NotEqual":
            return (op1 != op2);
        case "GreaterThan":
            return (op1 > op2);
        case "GreaterThanEqual":
            return (op1 >= op2);
        case "LessThan":
            return (op1 < op2);
        case "LessThanEqual":
            return (op1 <= op2);
        default:
            return (op1 == op2);            
    }
}
function CompareValidatorEvaluateIsValid(val) {
    var value = ValidatorGetValue(val.controltovalidate);
    if (ValidatorTrim(value).length == 0)
        return true;
    var compareTo = "";
    if (null == document.all[val.controltocompare]) {
        if (typeof(val.valuetocompare) == "string") {
            compareTo = val.valuetocompare;
        }
    }
    else {
        compareTo = ValidatorGetValue(val.controltocompare);
    }
    return ValidatorCompare(value, compareTo, val.operator, val);
}
function CustomValidatorEvaluateIsValid(val) {
    var value = "";
    if (typeof(val.controltovalidate) == "string") {
        value = ValidatorGetValue(val.controltovalidate);
        if (ValidatorTrim(value).length == 0)
            return true;
    }
    var args = { Value:value, IsValid:true };
    if (typeof(val.clientvalidationfunction) == "string") {
        eval(val.clientvalidationfunction + "(val, args) ;");
    }        
    return args.IsValid;
}
function RegularExpressionValidatorEvaluateIsValid(val) {
    var value = ValidatorGetValue(val.controltovalidate);
    if (ValidatorTrim(value).length == 0)
        return true;        
    var rx = new RegExp(val.validationexpression);
    var matches = rx.exec(value);
    return (matches != null && value == matches[0]);
}
function ValidatorTrim(s) {
    var m = s.match(/^\s*(\S+(\s+\S+)*)\s*$/);
    return (m == null) ? "" : m[1];
}
function RequiredFieldValidatorEvaluateIsValid(val) {
    return (ValidatorTrim(ValidatorGetValue(val.controltovalidate)) != ValidatorTrim(val.initialvalue))
}
function RangeValidatorEvaluateIsValid(val) {
    var value = ValidatorGetValue(val.controltovalidate);
    if (ValidatorTrim(value).length == 0) 
        return true;
    return (ValidatorCompare(value, val.minimumvalue, "GreaterThanEqual", val) &&
            ValidatorCompare(value, val.maximumvalue, "LessThanEqual", val));
}
function ValidationSummaryOnSubmit() {
    if (typeof(Page_ValidationSummaries) == "undefined") 
        return;
    var summary, sums, s;
    for (sums = 0; sums < Page_ValidationSummaries.length; sums++) {
        summary = Page_ValidationSummaries[sums];
        summary.style.display = "none";
        if (!Page_IsValid) {
            if (summary.showsummary != "False") {
                summary.style.display = "";
                if (typeof(summary.displaymode) != "string") {
                    summary.displaymode = "BulletList";
                }
                switch (summary.displaymode) {
                    case "List":
                        headerSep = "
";
                        first = "";
                        pre = "";
                        post = "
";
                        final = "";
                        break;
                    case "BulletList":
                    default: 
                        headerSep = "";
                        first = "
";
                        pre = "
";
                        post = "
";
                        final = "
";
                        break;
                    case "SingleParagraph":
                        headerSep = " ";
                        first = "";
                        pre = "";
                        post = " ";
                        final = "
";
                        break;
                }
                s = "";
                if (typeof(summary.headertext) == "string") {
                    s += summary.headertext + headerSep;
                }
                s += first;
                for (i=0; i";
                }
                for (i=0; i";
                                break;
                            case "BulletList":
                            default: 
                                s += "  - " + Page_Validators[i].errormessage + "
";
                                break;
                            case "SingleParagraph":
                                s += Page_Validators[i].errormessage + " ";
                                break;
                        }
                    }
                }
                span = document.createElement("SPAN");
                span.innerHTML = s;
                s = span.innerText;
                alert(s);
            }
        }
    }
}

System.Web.UI.Page Derived Page

using System;
using System.Text;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI;
using System.Collections.Specialized;
using System.Collections;

namespace Test.WebControls
{

	public class WebPage : System.Web.UI.Page
	{
		public WebPage()
		{
			validatorAssignments = new NameValueCollection();
		}

		private void Page_Load( object sender, System.EventArgs e )
		{
			if( this.validatorAssignments != null && this.validatorAssignments.HasKeys() )
			{
				StringBuilder sb = new StringBuilder();
				sb.Append("<script >");
				sb.Append(Environment.NewLine);
				sb.Append("Page_ValidatorAssignments = true;");
				sb.Append(Environment.NewLine);
				for( int i = 0; i < this.validatorAssignments.Count; i++ )
				{
					if( this.validatorAssignments.Keys[i].ToString() != string.Empty && this.validatorAssignments[i].ToString() != string.Empty )
					{
						sb.AppendFormat(" var {0}Validators = new Array(", this.validatorAssignments.Keys[i].ToString());
						string[] keys = this.validatorAssignments[i].Split(",".ToCharArray());
						for( int k = 0; k < keys.Length; k++ )
						{
							sb.AppendFormat("'document.all[\"{0}\"]'", keys[k].Trim());
							if( k != keys.Length - 1 )
								sb.Append(",");
						}
						sb.Append(");");
						sb.Append(Environment.NewLine);

					}
				}
				sb.Append(Environment.NewLine);
				sb.Append("</script>");
				Page.RegisterClientScriptBlock("ValidatorAssignments", sb.ToString());
			}
		}

		public override void Validate()
		{
			for( int i = 0; i < this.validatorAssignments.Count; i++ )
			{
				if( Request.Form[this.validatorAssignments.Keys[i].Replace("_", ":")] != null )
				{
					ArrayList assignedValidators = new ArrayList(this.validatorAssignments[i].Split(",".ToCharArray()));
					for( int k = 0; k < this.Validators.Count; k++ )
					{
						BaseValidator bv = (BaseValidator)this.Validators[k];
						if(!assignedValidators.Contains(bv.ClientID))
						{
							bv.Enabled = false;
						}
					}
					break;
				}
			}

			base.Validate();
			
		}

		private void InitializeComponent()
		{    
			this.Load += new System.EventHandler(this.Page_Load);
		}

		protected override void OnInit(EventArgs e)
		{
			InitializeComponent();
			base.OnInit(e);
		}

		public NameValueCollection ValidatorAssignments
		{
			get
			{
				return validatorAssignments;
			}
			set
			{
				validatorAssignments = value;
			}
		}
		

		private NameValueCollection validatorAssignments = null;	

	}
}

Test ASPX Page

	
		
		<script >
		// Returns the index of the "value" in the given array.
		// Returns -1 if not found in array.
		function InArray(array, value, attribute)
		{	
			if( attribute != null )
				attribute += ".";
				
			for(var i = 0; i < array.length;i++)
			{
				if( eval('array[i].' + attribute + 'toString().toLowerCase()') == value.toString().toLowerCase() )
					return i;
			}
			return -1;
		}
		</script>
	
	
		

			
			
			
			
			
		</form>
	

Test ASPX.CS Page

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;

namespace Test.TestDrivers
{
	/// 

	/// Summary description for ValidatorAssignmentTest.
	/// 
	public class ValidatorAssignmentTest : Test.WebControls.WebPage
	{
		protected System.Web.UI.WebControls.RequiredFieldValidator rfv1;
		protected System.Web.UI.WebControls.Button Button1;
		protected System.Web.UI.WebControls.RequiredFieldValidator rfv2;
		protected System.Web.UI.WebControls.Button Button2;
		protected System.Web.UI.WebControls.TextBox TextBox2;
		protected System.Web.UI.WebControls.TextBox TextBox1;
	
		private void Page_Load(object sender, System.EventArgs e)
		{
			// Put user code to initialize the page here
		}

		#region Web Form Designer generated code
		override protected void OnInit(EventArgs e)
		{
			//
			// CODEGEN: This call is required by the ASP.NET Web Form Designer.
			//
			InitializeComponent();
			this.ValidatorAssignments.Add("Button1", "rfv1");
			this.ValidatorAssignments.Add("Button2", "rfv2");
			base.OnInit(e);
		}
		
		/// 

		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// 
		private void InitializeComponent()
		{    
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion
	}
}

Jon