I have a FileUpload control to upload a certificate file. The user has to upload the file the first time, in subsequent visits to the page, we display the certificate content on the page, so it's not necessary to upload a file again.
Now I want to validate that a certificate is uploaded at least at once. The rest of the page uses ASP.NET validation controls so I want to go ahead with the same.
I can't use a RequiredFieldValidator on the FileUpload, because then it will fire everytime I try to save the page, which is wrong.
I tried using a CustomValidator and used the serverside validation, but seems that too fires only if I click on the file uploader. If I just leave it alone, the server side validation is not triggered.
I can of course do the validation on the [Save] button click event, but is there a proper way to do that using the validator events themselves?
CustomValidator:
<asp:CustomValidator ID="cusCertifacteExistanceValidator" runat="server" ValidationGroup="ConfigValidation" CssClass="errorMsg" ControlToValidate="fcertificate" Enabled="false" ErrorMessage="Certificate is not available" OnServerValidate="ValidateCertificateUpload">*</asp:CustomValidator>
CustomValidator Server side validation:
protected void ValidateCertificateUpload(object source, ServerValidateEventArgs args)
{
args.IsValid = false;
var existingCertificate = string.Empty;
if (ViewState["loginProviderProperties"] != null)
{
existingCertificate = ((List<Configuration>)ViewState["properties"]).Find(p => p.Name == "certificate").Value;
}
if (fX509Certificate.HasFile || existingCertificate != string.Empty)
{
args.IsValid = true;
}
}
It is very dificult to imagine without the code but My guess would be to add
ValidateEmptyText="true"
to custom validator.
Related
I'm having an issue with the cycle of a page reload and I can't figure it out. I have an ASP button the runs at the server but it has an associated client side click. The client side Javascript is running correctly and returning true to the button click so it is also running. The Javascript makes a modification to the query string on the URL and this is also working. However, in the C# code behind, the query string is not there. Somewhere, I'm missing something.
The HTML link:
<asp:Button ID="btnRunMOReport" class="button-dbg" runat="server"
Text="Run MO Report" OnClick="btnMO_Report_Click"
OnClientClick="return validateCheckBoxesMO()" />
The JavaScript portion:
function validateCheckBoxesMO() {
token='xyz';
let url1 = window.location.href;
if (url1.indexOf("?") > 0) {
url1 = url1.substring(0, url.indexOf("?"));
}
url1 += "?hiddenToken=" + token;
window.location.replace(url1);
return true;
}
The hiddenToken is now represented on the page (?hiddenToken=xyz).
The code behind:
protected void btnMO_Report_Click(object sender, EventArgs e)
{
MailMessage mailtest = new MailMessage();
mailtest.IsBodyHtml = true;
SmtpClient SmtpServertest = new SmtpClient(ConfigurationManager.AppSettings["smtp_server"]);
mailtest.To.Add("Whoever#test123.com");
mailtest.From = new MailAddress("Whoever#test123.com");
mailtest.Subject = Request.QueryString["hiddenToken"];
mailtest.Body = "Whatever";
}
The mail comes just fine but the subject is blank. Somehow, during the page reload cycle, the query string has not yet been set.
If there is a better way to pass data from the JavaScript to the code behind, I'm all ears.
I want to launch another page from the code behind but I need some data that is returned from the JS. The token is actually something I fetch, process the JSON and now I want to make that token available to the code behind for additional information to add to the new URL I am constructing. Probably TMI for this but it is what I am trying to do.
Thanks for your assistance.
Your script isn't working because the browser makes a POST request to submit the form (and __VIEWSTATE) using the action="" attribute of the <form> that WebForms adds to your page.
When your client-script sets window.location it isn't changing how the <form> will behave. You could use your script to append the new querystring value to the <form>'s action="" attribute and this may work, however it will likely fail if the application has request-validation enabled (in which case ASP.NET will reject a tampered form submission).
As you're using WebForms (and you shouldn't be using WebForms in 2021...) you shouldn't try to fight it unless you understand how it all works (I'm not trying to be condescending: it took me years to figure it all out and I've been using WebForms since 2004).
Instead, provide the value through an <asp:HiddenField>:
Change your .aspx markup to this:
<asp:Button runat="server" ID="btnRunMOReport" class="button-dbg"
Text="Run MO Report" OnClick="btnMO_Report_Click"
OnClientClick="return validateCheckBoxesMO()" />
<asp:HiddenField runat="server" ID="superSecretHiddenField" />
Change your client script to this:
function validateCheckBoxesMO() {
const hiddenFieldId = '<%= this.superSecretHiddenField.ClientID %>';
const hiddenField = document.getElementById( hiddenFieldId );
token='xyz';
hiddenField.value = token;
return true; // <-- This is wrong, btw. Instead use `Event.prototype.stopPropagation()` - but that requires the on-click function to be wired-up correctly and I don't remember the specifics other than that WebForms *doesn't* do things correctly (not out-of-spite, but because WebForms predates the standardisation of client-script events).
}
And your code-behind to this:
protected void btnMO_Report_Click(object sender, EventArgs e)
{
MailMessage mailtest = new MailMessage();
mailtest.IsBodyHtml = true;
SmtpClient SmtpServertest = new SmtpClient(ConfigurationManager.AppSettings["smtp_server"]);
mailtest.To.Add("Whoever#test123.com");
mailtest.From = new MailAddress("Whoever#test123.com");
mailtest.Subject = this.superSecretHiddenField.Value;
mailtest.Body = "Whatever";
}
As noted, a button post back will in general over-write the url that you change. Unless you actually do a navigation client side that is caused by the js, then it will not persist.
So, on the most simple level, just drop in a text box, or hidden field, and put the value you need/want into that hidden textbox or field.
So, client side? Markup?
You can use this:
<asp:Button ID="Button1" runat="server" Text="Delete"
OnClientClick="SetHidden();"/>
<asp:HiddenField ID="HiddenField1" runat="server" ClientIDMode="Static"/>
<br />
<script>
function SetHidden() {
hField = document.getElementById('HiddenField1');
hField.value = 'zoo';
return true;
}
</script>
So in above, we set our value in js to zoo, and of course we do return true. If we return false then the asp.net button code server side will not run - so we can control this, or even say pop up a confirm dialog and return true/false based on that to control if the server side code behind will run.
Server side, code behind? You can now use this:
Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Debug.Print(HiddenField1.Value)
End Sub
So the above is easy, clean. You can also use a text box, and set the style="display:none", but a hidden field is just as well and easy.
I am using a jQuery editor and when the user hits the submit button i put the content into asp.net Panel control as html and then when i render this Panel the html i added is not
retrieved.
function MoveData() {
var sHTML = $('#summernote_1').code();
// dvFrontPageHtml is asp.net Panel
$('[id*=dvFrontPageHtml]').html(sHTML);
setTimeout(function () {
javascript: __doPostBack('ctl00$ctl00$ContentPlaceHolderBody$ContentPlaceHolderBody$lnkSave', '');
}, 10000);
return false;
}
System.Text.StringBuilder sb = new System.Text.StringBuilder();
System.IO.StringWriter stWriter = new System.IO.StringWriter(sb);
System.Web.UI.HtmlTextWriter htmlWriter = new System.Web.UI.HtmlTextWriter(stWriter);
dvFrontPageHtml.RenderControl(htmlWriter);
string Message = sb.ToString();
The message does not returning the html added.
I dont want to use jQuery ajax call as of now.
Any suggestions
without seeing all the relevant code its hard to pinpoint the problem.
but im pretty sure you are trying to find an ASP.net control by its serverside ID from clientside.
dvFrontPageHtml is the Controls ID by which asp.net identifies it, and unless you explicitly tell ASP.Net otherwise, it will generate a different ID for the control to be used by scripts at clientside
you need to retrieve the panel's clientside ID thats being generated for it by asp.net
you do it by a preprocessor directive <%=dvFrontPageHtml.ClientID%>:
$('[id*=<%=dvFrontPageHtml.ClientID%>]').html(sHTML);
alternatively, if you want the clientside ID to be same as the serverside ID, you can set the control's attribute ClientIDMode="Static".
UPDATE:
from your comment it seems the problem is elsewhere. what comes to mind, is that RenderControl() takes the control as it was when sent to the client in the Response. but the control is not being submitted to the server in next Request, so you will not be able to retrieve its altered html.
what you can do as a workaround, is hook into ASP.NET's build in postback mechanism, and submit the panel's html as a custom event argument:
for the example, lets assume this is our html:
<asp:Panel ID="dvFrontPageHtml" runat="server" ClientIDMode="Static">test</asp:Panel>
<asp:Button ID="BT_Test" runat="server" Text="Button"></asp:Button>
this will be our javascript:
$(function(){
// add custom event handler for the submit button
$("#<%=BT_Test.ClientID%>").click(function (ev) {
//prevent the default behavior and stop it from submitting the form
ev.preventDefault();
//alter the panels html as you require
var sHTML = $('#summernote_1').code();
$('[id*=dvFrontPageHtml]').html(sHTML);
//cause a postback manually, with target = BTCLICK and argument = panel's html
__doPostBack('BTCLICK', $('[id*=dvFrontPageHtml]').outerHTML());
});
});
and here we capture the postback on serverside:
//we monitor page load
protected void Page_Load(object sender, EventArgs e)
{
string Message;
//check if its a postback
if (IsPostBack)
{
//monitor for our custom target "BTCLICK"
if (Request.Form["__EVENTTARGET"].CompareTo("BTCLICK") == 0)
{
// retrieve the panels html from the event argument
Message = Request.Form["__EVENTARGUMENT"];
}
}
}
We're trying to build a simple asp control for some clients where they can just drop in a single block -
i.e.
<captcha:CaptchaControl ID="CaptchaControl1"
runat="server"
Server="http://localhost:51947/"
/>
and have it render the control. The catch is that I can't get this to include custom validation. Right now I'm using the RenderContents function to display the layout of the control itself as well as hook it up the to Javascript. The problem is that I don't know how to get custom validation to fire when used as part of a control.
protected override void RenderContents(HtmlTextWriter output)
{
output.Write(#"
<script type=""text/javascript"" src=""http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js""></script>
<link rel=""stylesheet"" type=""text/css"" href=""/Layout/CaptchaLayout.css"" />
//etc
<asp:Textbox id=""text1"" runat=""server"" text=""""></asp:Textbox>
<asp:CustomValidator id=""CustomValidator2"" runat=""server""
ControlToValidate = ""text1""
ErrorMessage = ""You must enter at least 8 characters!""
ClientValidationFunction=""validateLength"" >
</asp:CustomValidator>"
);
}
Any suggestions for a better way to do this?
Oogh, I would definitely not recommend your approach. It's very brittle and difficult to maintain, and depending on how your control is used, I'm not even sure that you can output more asp tags and have them processed properly.
Why don't you just inherit your custom control from Panel, and then in the Init or Load event handlers, add the textbox and custom validator to it? Roughly:
public class MyControl : Panel
{
public MyControl()
{
}
protected override void OnInit(EventArgs e)
{
ScriptManager.RegisterScript( ... Google script, CSS, etc. ... );
TextBox txt = new TextBox();
txt.ID = "text1";
this.Controls.Add(txt);
CustomValidator vld = new CustomValidator();
vld.ControlToValidatre = "text1";
vld.ID = "validator1";
this.Controls.Add(vld);
}
}
Your CustomValidator doesn't work because ASP.NET has no idea it's there. You are basically just dumping that output to the response... ASP.NET is not interpreting it.
It seems to me that this is a perfect situation for a User Control rather than a Custom Control. Just drop that output string in its own .ASCX file.
When the page class property IsValid is read only, how can I set it using my own validation method?
So far all I've been able to do is set this property by calling Page.Validate().
How can I write my own functionality that will change the IsValid property just like Page.Validate()?
You don't set IsValid directly instead you call Validate() method of the Page object. If you have your custom validation methods then you need to use CustomValidator object and set that function in its server side validation property.
<asp:CustomValidator ID="YourValidator" runat="server" SetFocusOnError="true"
ControlToValidate="YourControl"
ClientValidationFunction="YOUR_JAVASCRIPT_FUNCTION"
OnServerValidate="YOUR_SERVER_VALIDATION_FUNCTION" Text="*" />
I know this is old, but, I needed to do something similar, basically forcing the IsValid property to false (don't ask why). Here is what I did basically (what you see here is my proof of concept):
Added this to the .aspx page:
<asp:TextBox ID="txtDummy" runat="server" Visible="false" />
<asp:RangeValidator ID="rvDummy" ControlToValidate="txtDummy" runat="server" MinimumValue="1" MaximumValue="2" />
And then I added this to the code behind:
bool makeMyPageInvalid = true;
if (makeMyPageInvalid)
txtDummy.Text = "0";
Page.Validate();
if (Page.IsValid)
ScriptManager.RegisterStartupScript(Page, Page.GetType(), "test", "alert('valid');", true);
else
ScriptManager.RegisterStartupScript(Page, Page.GetType(), "test", "alert('not valid');", true);
You can see that this only allows you to force the page validation to an invalid state. You can use any validator or reason to set this. Hope this helps someone!
The IsValid property is read-only because it is intended for use with server and client-side validators like the RequiredFieldValidator and RegularExpressionValidator. It's read-only because you can't force a page to be valid programmatically. "Valid" in this context means all the validators on the page evaluate to true.
If you feel like using some JavaScript you can do it in the client-side by modifying the variable Page_IsValid like this:
function pageLoad() {
Page_IsValid = false;
}
I use this just in case someone clicks the submit button w/o entering data. Then I can display an alert like this:
function valid() {
if (!Page_IsValid) {
alert("Some Questions Remain Unanswered and are Marked with a Red Asterisc. ( * )");
}
(at the beginning I thought 'who would submit a form w/o data' but sooner rather than later I realized it happens)
This is a really old question, but it came up in a search so I thought I'd add my answer to it. First, create an extension method in one of your helper classes.
public static IEnumerable<T> GetAllControlsOfType<T>(this Control parent) where T : Control
{
var result = new List<T>();
foreach (Control control in parent.Controls)
{
if (control is T)
{
result.Add((T)control);
}
if (control.HasControls())
{
result.AddRange(control.GetAllControlsOfType<T>());
}
}
return result;
}
Now in your code behind file, loop over every validator on the page that is not validating.
foreach (var validator in Page.GetAllControlsOfType<BaseValidator>().Where(w => !w.IsValid))
{
validator.IsValid = true;
}
Related Article
On a similar topic to the above article, but of a more specific note. How exactly do you handle items that are in the viewstate (so they are included on submit), but can also be changed via AJAX. For instance, say we had a dropdown list that was populated through an AJAX web service call (not an update panel). How can I get the page to validate once the dropdownlist's items have been changed?
You're not validating the dropdown list are you? You're validating the value a user selected. It's pretty much the same advice as the other post, since javascript or other tools can alter the html or create their own POST's, you must always validate on the server side. Assume all client requests can be tampered with, and assume that no client-side validation has occurred.
If you're using the web forms model ....
If you just want to check a value was selected in the dropdown myAjaxDropDown, use the
<asp:RequiredFieldValidator id="dropdownRequiredFieldValidator"
ControlToValidate="myAjaxDropDown"
Display="Static"
InitialValue="" runat=server>
*
</asp:RequiredFieldValidator>
You could also want to look at the asp:CustomValidator - for server side validation:
<asp:CustomValidator ID="myCustomValidator" runat="server"
onservervalidate="myCustomValidator_ServerValidate"
ErrorMessage="Bad Value" />
Both plug into the validation framework of asp.net. e.g. when you click a button called SumbitButton
protected void myCustomValidator_ServerValidate(object source, ServerValidateEventArgs e)
{
// determine validity for this custom validator
e.IsValid = DropdownValueInRange(myAjaxDropDown.SelectedItem.Value);
}
protected void SubmitButton_Click( object source, EventArgs e )
{
Validate();
if( !IsValid )
return;
// validators pass. Continue processing.
}
Some links for further reading:
ASP.Net 2.0 Quickstart - Validating Form Input Controls
ASP.NET Validation Controls – Important Points, Tips and Tricks
You can call the Page_Validate() function from your javascript code, it will trigger the asp.net validators on the page, it is basically similar to Page.Validate() in server code
why not validating onChange even in the dropdownlist?
just add the script manager and add that property to the onchange in the Page_Load event
' Creating the javascript function to validate
Dim js As String
js = "function validateDDL1(ddl) { alert(ddl.value); }"
' Adding onChange javascript method
DropDownList1.Attributes.Add("onchange", "validateDDL1(this);")
' Registering the javascript
ScriptManager.RegisterClientScriptBlock(Me, GetType(String), "validateDDL1(ddl)", js, True)