寫一個非同步驗證控制項

 

AjaxValidator.js

function AjaxValidatorEvalateValid(val) {      var value = ValidatorGetValue(val.controltovalidate);      WebForm_DoCallback(val.id, value, AjaxValidatorResult, val, AjaxValidatorError, true);}function AjaxValidatorResult(returnValue, context) {      if (returnValue == "True") {            context.isvalid = true;      }      else {            context.isvalid = false;      }      ValidatorUpdateDisplay(context);}function AjaxValidatorError(message) {      alert("Error:" + message);}

 

AjaxValidator.cs

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;/// <summary>///AjaxValidator 的摘要說明/// </summary>public class AjaxValidator:BaseValidator,ICallbackEventHandler{      public event ServerValidateEventHandler ServerValidate;      private string _controlToValidate;      public AjaxValidator()      {            //            //TODO: 在此處添加建構函式邏輯            //      }      protected override void OnPreRender(EventArgs e)      {            string eventRef = Page.ClientScript.GetCallbackEventReference(this, "", "", "");            string includeScript = Page.ResolveClientUrl("~/ClientScripts/AjaxValidator.js");            Page.ClientScript.RegisterClientScriptInclude("AjaxValidator", includeScript);            //註冊驗證控制項所觸發的方法            string startScript = String.Format("document.getElementById('{0}').evaluationfunction='AjaxValidatorEvalateValid';", this.ClientID);            Page.ClientScript.RegisterStartupScript(this.GetType(), "AjaxValitator", startScript, true);            base.OnPreRender(e);      }      protected override bool DetermineRenderUplevel()      {            return Context.Request.Browser.SupportsCallback;      }      protected override bool EvaluateIsValid()      {            string contraolToValidateValue = this.GetControlValidationValue(this.ControlToValidate);            return ExecuteValidationFunction(contraolToValidateValue);      }      #region ICallbackEventHandler 成員      public string GetCallbackResult()      {            return ExecuteValidationFunction(_controlToValidate).ToString();      }      public void RaiseCallbackEvent(string eventArgument)      {            _controlToValidate = eventArgument;      }      #endregion      private bool ExecuteValidationFunction(string controlToValidateValue)      {            ServerValidateEventArgs args = new ServerValidateEventArgs(controlToValidateValue, this.IsValid);            if (ServerValidate != null)            {                  ServerValidate(this, args);            }            return args.IsValid;      }}

 

用上面的驗證控制項就可以輕鬆實現非同步驗證了