ASP.NET MVC3: Razor GetHTML Table custom layout - asp.net

Im manually Creating the table using the built in razor GETHtml Function.
#table.GetHtml(
columns: table.Columns(
table.Column("Account"),
table.Column("Due"),
table.Column("Topic"),
table.Column("Type"),
table.Column("Completed?", format: #<input id="Complete" name="Complete" type="checkbox" onclick="/Tasks/Complete?ID=700" />)
)
)
What I want is a way of clicking a checkbox, or button to activate the controller. it is not accepting Dynamic checkbox. Nor does the html checkbox do anything.

I Have a working solution without using forms, the column would be set using the following code:
table.Column("Completed?", format: #<input type="checkbox" onclick="location.href='#Url.Action("Complete", "Tasks", new { TaskID = item.TaskID })'" />
I think its possible that having the name property was causing it to post it as a parameter, rather than treat it as a submit.
Otherwise it must ahve been the onclick event. Ive used location.href, then set it using razor syntax, and included the id as a property.

Couple of ways to go about performing a post to your desired controller. Wrap your table with the form you would like to submit or add a few AJAX handlers to post the data you desire. A simple form could be accomplished like:
<% using (Html.BeginForm<SomeController>(x=> x.SomeAction())
{
#table.GetHtml(
columns: table.Columns(
table.Column("Account"),
table.Column("Due"),
table.Column("Topic"),
table.Column("Type"),
table.Column("Completed?", format: #<input id="Complete" name="Complete" type="submit" " />)
)
)
}

Related

GWT - Get the value of a checkbox from a servlet [duplicate]

I have an html form and i would like ALWAYS to have checkboxes to submit a value. How can i do that? I have one idea but i havent tried it and i am unsure if its the best way to do it (jquery to check if the box is checked or not, then set the value to 0/1 and check it off so it will submit)
Thanks to #Lazarus' idea, also mentioned by #BalusC, you can add an additional control to the form:
<input type="hidden" name="checkbox1" value="off">
<input type="checkbox" name="checkbox1" value="on"> My checkbox
Checkbox and the hidden fields must have the same name. The hidden input is always submitted as a default value. If the checkbox is checked then also it's submitted. So you have a list of 2 values for parameter "checkbox1", that you have to treat at server side.
...maybe a <select> tag would be more handy.
There is a legitimate reason for asking for something like this, although the behaviour envisioned here is not the right way to go about it. There is a problem with the checkbox when used correctly when editing existing data and that's that there is no way to determine whether no value was submitted because the field was not present on the form or because the user cleared all of the values. You can run into this sort of problem any time you include fields conditionally.
One could go to the trouble of maintaining a "view state", of course, but it's much easier to include a hidden "companion field" whenever a checkbox or select with the multiple option (which is also excluded when all selections are cleared) is displayed. The field should have a related but different name (a name from which the actual field name can be extracted). The Lotus Domino server has used fields named %%Surrogate_FieldNameHere for this purpose since (I believe) version 7 for exactly the reason I described here.
To tell you the truth, this feels like a big no-no.
Anyway here goes:
<script type="text/javascript">
$(document).ready(function () {
$('form').submit(function() {
$(this).find('input[type=checkbox]').each(function () {
$(this).attr('value', $(this).is(':checked') ? '1' : '0');
$(this).attr('checked', true);
});
});
});
</script>
HTML doesn't work that way. HTML checkboxes are specified as follows: if checked, then its name=value will be sent as request parameter. If unchecked, then its name=value will not be sent as request parameter. Note that when the value is unspecified, then most browsers default to "on". It's easier if you give all checkboxes the same name but a different and fixed value. This way you can obtain the checked ones as an array/collection.
If all checkboxes are already known beforehand in server side, you can just apply basic math to obtain the unchecked checkboxes:
uncheckedCheckboxes = allCheckboxes - checkedCheckboxes
If those checkboxes are created dynamically at the client side and therefore unknown beforehand in server side, then add for each checkbox a <input type="hidden"> field containing information about the dynamically created checkbox, so that the server side knows which checkboxes are all present as the moment of submission.
Although this goes against the HTML spec, if you know what you are doing, using this you no longer have to cater checkboxes which are handled completely differently when submitted - and for example naming fields with_brackets[] can actually be useable.
Complete solution
$(document).on('submit', 'form', function() {
$(this).find('input[type=checkbox]').each(function() {
var checkbox = $(this);
// add a hidden field with the same name before the checkbox with value = 0
if ( !checkbox.prop('checked') ) {
checkbox.clone()
.prop('type', 'hidden')
.val(0)
.insertBefore(checkbox);
}
});
});
Take note: the non-checked checkboxes now submit a value of "0"
Additionally, if you want to change the behaviour of a single form only, just alter the first line in the above snippet:
$(document).on('submit', 'form.your-class-name', function() {
// ...
});
if you have many checkbox, you can try this code:
<input type="checkbox" onclick="$(this).next().val(this.checked?1:0)"/> <input type="hidden" name="checkbox1[]"/>
If you have the following HTML:
<form id="myform" method="post" action="my/url">
<input type="checkbox" id="checkbox1" name="checkbox1"/>
<input type="checkbox" id="checkbox2" name="checkbox2"/>
<input type="checkbox" id="checkbox3" name="checkbox3"/>
</form>
Normal form submit:
On form submit, before submitting, change all values of checkboxes to 0 and 1 based on if checkbox is unchecked or checked. Like so:
$('#myform').submit(function() {
var $checkboxes = $('#myform').find('input[type="checkbox"]');// Select all checkboxes
$checkboxes.filter(':checked').val(1);// Set value to 1 for checked checkboxes
$checkboxes.not(':checked').val(0);// Set value to 0 for unchecked checkboxes
$checkboxes.prop('checked', true);// Change all checkboxes to "checked" so all of them are submitted to server
});
Note: Ugly thing about this code, while form is submitting, all checkboxes will appear as "checked" for a moment. But if you apply same concept for ajax form submit, it would be better.
AJAX form submit:
$.post('my/url', {
'checkbox1': $('#checkbox1').is(':checked') ? 1 : 0,
'checkbox2': $('#checkbox2').is(':checked') ? 1 : 0,
'checkbox3': $('#checkbox3').is(':checked') ? 1 : 0
}, function(response) {
// Server JSON response..
}, 'json');

asp.net mvc Redirect to action without triggering validation in current view?

I have a view which has multiple submit buttons. One button is for going back to another action which does some processing and load previous view.
However, in current view, it has some validations for model. So, when the button is click, it will show validation error.
Is there a way to get around this? or, we have to validate the data on server side?
Thanks
The built in client side validation in ASP.NET MVC uses the jquery validation plugin under the hood where you can skip validation while still using a submit-button with adding class="cancel" to that input:
<input type="submit" value="Do not validate" class="cancel" />
See this also in the documentation.
You can cancel validation by doing this:
$('#yourButton').click(function() {
$('input, textarea, select', '#yourForm').each(function () {
$(this).attr('data-val', 'false');
});
})
or
$("#yourButton").click(function() {
$('#yourForm').removeData('validator');
$('#yourForm').removeData('unobtrusiveValidation');
$('#yourForm').validate().cancelSubmit = true;
$('#yourForm').submit();
});
class ="cancel" is now replaced by formnovalidate attribute

MVC3 webgrid filtering advice?

I'm trying to figure out the best way (minimal effort) to apply filtering to a webgrid that I have displayed in my Main/Index view (MVC3).
I added a multiselet that would allow filtering by a certain column and I would like to catch the click event (which I already have implemented and working) per select item and then somehow re-invoke my Index() method that contains all the code to rebuild the view based on if it was invoked from a filter (multiselect).
What is the best way to go about this? I know that this is a broad ask but any information would be greatly appreciated.
Thanks!
You could place the multiselect inside a form. Then you have 2 possibilities to submit this form:
Using a submit button
Using the onchange event of the multiselect (in this case you will have to use javascript)
The first point is straightforward:
#using (Html.BeginForm())
{
#Html.ListBoxFor(x => x.SelectedItems, Model.Items)
<button type="submit">Filter</button>
}
To implement the second you could use jQuery and subscribe to the change event of the multiselect. First, let's give this multiselect an id so that we can more easily select it:
#using (Html.BeginForm())
{
#Html.ListBoxFor(x => x.SelectedItems, Model.Items, new { id = "filter" })
}
and then in a separate javascript file:
$(function() {
$('#filter').change(function() {
// when the selection changes we manually trigger the submission
// of the containing form
$(this).closest('form').submit();
});
});
In both cases the controller action that we are submitting to will take an array of strings as argument which will represent the selected values in the multiselect which will be used to filter the resultset.

Range validation

Suppose I have a table like:
create table
{
id numeric(5,3),
code varchar(10)
}
I have two text boxes in my form for the two fields.
Suppose if I type 1234578 in the first text box the error has been thrown in ASP.NET because I crossed the limit.
How can I validate in JavaScript or some other way for that particular range validation?
Let's take one textbox only. Attach an 'onchange' event handler to your textbox like this:
<input type="text" onchange="handleChange(this);" />
Then declare a script for validation like this:
<script>
function handleChange(input) {
if (input.value > ..your_value_here..) alert ("Invalid input");
}
</script>
Please note that the alert pop-up used here should not be actually used. Use a more subtle reminder at a more appropriate moment. The alert here is only to make things simple.

Passing hidden field from one page to another in querystring

I want to pass a query in a hidden filed from 1 page to another by querystring.
Can anyone help me out with the logic?
It's worth taking the time to learn jQuery. It's not very complicated, and it makes writing javascript much easier. There are also many jQuery plugins, such as jquery.url.
Also, as other posters have suggested, you may not wish to put the hidden field's value in the query string if you care about it being displayed to the user. However, if the data is present in a hidden field it will always be possible for a user to find it if they care to look.
If you really do want to put the hidden field in the query string and then extract it via non-jQuery javascript:
hiddenFieldPage.aspx
This form will take the user to processingPage.aspx?datum=someValue when it is submitted. You could probably also just use an ordinary link if nothing else needs to be submitted at the same time.
<form method="GET" action="processingPage.aspx">
<input type="hidden" name="datum" value="someValue">
<input type="submit">
</form>
or, inserting the value from code-behind:
RegisterHiddenField("datum", "someValue");
processingPage.aspx
This script will pop-up an alert box with the value of "datum" from the URL - assuming the form's method is set to "GET":
<script type="text/javascript">
function getUrlParam( key ) {
// Get the query and split it into its constituent params
var query = window.location.search.substring(1);
var params = query.split('&');
// Loop through the params till we find the one we want
for( var i in params ) {
var keyValue = params[i].split('=');
if( key == keyValue[0] ) {
return keyValue[1];
}
}
// Didn't find it, so return null
return null;
}
alert( getUrlParam("datum") );
</script>
If the form's method was set to "POST" (as it usually would be in ASP.NET), then "datum" won't be in the query string and you'll have to place it on the page again:
RegisterHiddenField( "datum", Request.Form["datum"] );
To retrieve the hidden value on the second page:
var datum = document.Form1.item("datum").value;
alert( datum );
You can easily submit a form on one page that points to another page using the action parameter. For instance, inside of page1.aspx put the following:
<form action="page2.aspx" method="GET">
<input type="hidden" name="username" value="joenobody" />
<input type="submit" />
</form>
Since you're using "GET" as the method instead of "POST", you could potentially use Javascript to parse the URL and get the value that was passed. Alternatively, you could use ASPX to store the value of the "username" field somewhere else on the page. I don't know ASPX (or ASP, or anything Microsoft really), but if you can find a way to output something like the following (and are using jQuery), it may do what you require. Honestly though, it sounds like you are going about something all wrong. Can you modify your question to be a bit more specific about what the general object is that you are attempting to accomplish?
<div id="some_div"><%= Request.form("username") %></div>
<script type='text/javascript'>
var value_needed = $('#some_div').html();
</script>
<form method="get">
Assuming you mean hidden in the HTML form sense, your field will be submitted along with all the other fields when the form is submitted. If you are submitting via GET, then your "hidden" field will show up in plain text in the URL. If you don't want the data in the hidden field to be accessible to users, don't put an understandable value in that field.
If you are using aspx, you do not need to parse the query string using JavaScript, or even use <form method="GET" ...>. You can POST the form to the second aspx page, extract the value in C# or VB then write it to a client-side JavaScript variable. Something like this:
page1.aspx:
<form method="POST" action="page2.aspx">
<input type="hidden" name="myHiddenServerField" value="myHiddenServerValue">
<input type="submit">
</form>
page2.aspx:
<script type="text/javascript">
var myHiddenClientValue = '<%= Request.Form['myHiddenServerField']; %>';
</script>
The above would set the client-side JavaScript variable called myHiddenClientValue to a value of 'myHiddenServerValue' after the POST.
This can be a bad idea because if myHiddenServerField contains single quotes or a newline character, then setting it on the client in page2.aspx can fail. Embedding ASP.NET Server Variables in Client JavaScript and Embedding ASP.NET Server Variables in Client JavaScript, Part 2 deals with specifically these issues, and solves them with a server-side class that ensures values being written to the client are escaped correctly.
If you use method="get" on an HTML form then any hidden inputs in that form will be converted to query parameters.
See also Jeremy Stein's answer.

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