CustomValidator.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / DotNET / DotNET / 8.0 / untmp / whidbey / REDBITS / ndp / fx / src / xsp / System / Web / UI / WebControls / CustomValidator.cs / 1 / CustomValidator.cs
                        

                        
                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Web.UI.WebControls { 
 
    using System.ComponentModel;
    using System.Web; 
    using System.Security.Permissions;
    using System.Web.Util;

 
    /// 
    ///     Allows custom code to perform 
    ///       validation on the client and/or server. 
    /// 
    [ 
    DefaultEvent("ServerValidate"),
    ToolboxData("<{0}:CustomValidator runat=\"server\" ErrorMessage=\"CustomValidator\">")
    ]
    [AspNetHostingPermission(SecurityAction.LinkDemand, Level=AspNetHostingPermissionLevel.Minimal)] 
    [AspNetHostingPermission(SecurityAction.InheritanceDemand, Level=AspNetHostingPermissionLevel.Minimal)]
    public class CustomValidator : BaseValidator { 
 
        private static readonly object EventServerValidate= new object();
 

        /// 
        ///    Gets and sets the custom client Javascript function used
        ///       for validation. 
        /// 
        [ 
        WebCategory("Behavior"), 
        Themeable(false),
        DefaultValue(""), 
        WebSysDescription(SR.CustomValidator_ClientValidationFunction)
        ]
        public string ClientValidationFunction {
            get { 
                object o = ViewState["ClientValidationFunction"];
                return((o == null) ? String.Empty : (string)o); 
            } 
            set {
                ViewState["ClientValidationFunction"] = value; 
            }
        }

 
        [
        WebCategory("Behavior"), 
        Themeable(false), 
        DefaultValue(false),
        WebSysDescription(SR.CustomValidator_ValidateEmptyText), 
        ]
        public bool ValidateEmptyText {
            get {
                object o = ViewState["ValidateEmptyText"]; 
                return((o == null) ? false : (bool)o);
            } 
            set { 
                ViewState["ValidateEmptyText"] = value;
            } 
        }


        ///  
        ///    Represents the method that will handle the
        ///     event of a 
        ///    . 
        /// 
        [ 
        WebSysDescription(SR.CustomValidator_ServerValidate)
        ]
        public event ServerValidateEventHandler ServerValidate {
            add { 
                Events.AddHandler(EventServerValidate, value);
            } 
            remove { 
                Events.RemoveHandler(EventServerValidate, value);
            } 
        }


        ///  
        /// 
        /// Adds the properties of the  control to the 
        ///    output stream for rendering on the client. 
        /// 
        protected override void AddAttributesToRender(HtmlTextWriter writer) { 
            base.AddAttributesToRender(writer);
            if (RenderUplevel) {
                string id = ClientID;
                HtmlTextWriter expandoAttributeWriter = (EnableLegacyRendering) ? writer : null; 

                AddExpandoAttribute(expandoAttributeWriter, id, "evaluationfunction", "CustomValidatorEvaluateIsValid", false); 
                if (ClientValidationFunction.Length > 0) { 
                    AddExpandoAttribute(expandoAttributeWriter, id, "clientvalidationfunction", ClientValidationFunction);
                    if (ValidateEmptyText) { 
                        AddExpandoAttribute(expandoAttributeWriter, id, "validateemptytext", "true", false);
                    }
                }
            } 
        }
 
 
        /// 
        ///  
        ///    Checks the properties of the control for valid values.
        /// 
        protected override bool ControlPropertiesValid() {
            // Need to override the BaseValidator implementation, because for CustomValidator, it is fine 
            // for the ControlToValidate to be blank.
            string controlToValidate = ControlToValidate; 
            if (controlToValidate.Length > 0) { 
                // Check that the property points to a valid control. Will throw and exception if not found
                CheckControlValidationProperty(controlToValidate, "ControlToValidate"); 
            }
            return true;
        }
 

        ///  
        ///  
        ///    EvaluateIsValid method
        ///  
        protected override bool EvaluateIsValid() {

            // If no control is specified, we always fire the event. If they have specified a control, we
            // only fire the event if the input is non-blank. 
            string controlValue = String.Empty;
            string controlToValidate = ControlToValidate; 
            if (controlToValidate.Length > 0) { 
                controlValue = GetControlValidationValue(controlToValidate);
                Debug.Assert(controlValue != null, "Should have been caught be property check"); 
                // If the text is empty, we return true. Whitespace is ignored for coordination wiht
                // RequiredFieldValidator.
                if ((controlValue == null || controlValue.Trim().Length == 0) &&
                     !ValidateEmptyText) { 
                    return true;
                } 
            } 

            return OnServerValidate(controlValue); 
        }


        ///  
        ///    Raises the
        ///     event for the . 
        ///  
        protected virtual bool OnServerValidate(string value) {
            ServerValidateEventHandler handler = (ServerValidateEventHandler)Events[EventServerValidate]; 
            ServerValidateEventArgs args = new ServerValidateEventArgs(value, true);
            if (handler != null) {
                handler(this, args);
                return args.IsValid; 
            }
            else { 
                return true; 
            }
        } 
    }
}

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