Is there a way to can access and manipulate the POST params after a form submit has been made. To be more specific, in my submit event handler, how can I do something like
$("#form").submit()
{
//access the request params and manipulate them here
return true;
}
instead of the following hack which I find to be not that elegant.
$("#submit_button").click()
{
// Construct the Request 'params' manually
$.post("/foo/action", params, redirectIfSuccess);
}
You can do it before form submit. Just check the variables in the form on submit event change one or more of them and submit with new data.
$("#form").submit(function() {
$("#form #myInputField").val("Some text here");
return true;
});
With ("#myInputField") you select the input field or you can use ("input[name='myInputField']") to select a input on its name attribute.
After that you can use val() to get or val("Some text") to set the value of the appropriate input. That's all.
To add new input or DOM element you have to use .append(),
Ex:
$("#form").append("<input type="hidden" name="myNewInput" value="1" />");
Have a look here: http://api.jquery.com/append/
Related
I have the below jQuery function which is called when ever I click a button on my page. This button is supposed to reset the form and reload a fresh page.
function Create(txt) {
if (txt="createUser") {
document.forms[0].reset();
$('#myform').each(function() {
this.reset();
});
$('input[name=method]').val(txt);
document.forms[0].submit();
}
}
But for some reason, it does not go to this.reset() at all and I see all the form values in my action class. How should I solve this?
Below is how the button is defined.
<input type="button" value="Create" class="btn" onclick="Create('createUser');">
edit: Ok guys.. i know how input type="reset" works and i have another button in my page doing the same.. I have a create user form where i can search and see an existing user details or fill the form and create a new user. if i search for a user and then click on create to create another user, it sends a new request to the server and reloads the page.. but in the action class.. the bean has not been reset.. and i get all the values back on the page. hence ..i want to reset the form...without using the reset button...
I selected John's answer .. made a slight modification and below is the final function i used.
function Create(txt){
if (txt="createUser"){
var $form = $('#myform');
$form.find(':input').not(':button,:submit, :reset, :hidden').val('').removeAttr('checked').removeAttr('selected'); // Clear all inputs
$form.find('input[name=method]').val(txt);
$form.submit();
}
}
Instead of java script, you can have html code,
<input type="reset" value="Reset">
As others have pointed out, you have = where you should have ==, but that means the if-statement is always true. It is not, however, the reason you "see all the form values in my action class".
I think the problem may be that you are misinterpreting what the reset() method does. It does not clear all the input values; instead, it resets them to their original values (i.e., the values in the "value" attributes).
You may want to clear them yourself, rather than use the reset() method.
function Create(txt) {
if (txt == 'createUser') {
var $form = $('#myform');
// Clear form values
$form.find(':input:not(:button,:submit,:reset,:checkbox,:radio,:hidden)').val('');
$form.find('input:checkbox,input:radio)').prop('checked', false);
$form.find('input[name=method]').val(txt);
$form.submit();
}
}
Note: The :input selector matches all input, textarea, select and button elements.
Note: It appears the OP does not want hidden inputs to be cleared, but does want checkboxes and radio buttons cleared.
You seem to be setting a variable here -
if (txt="createUser"){...
Change it to -
if (txt == "createUser") {..
That way you're doing a comparison, instead of setting a variable.
the button does not have type="reset" so either change it to reset or use
document.getElementById("myform").reset(); instead of
document.forms[0].reset();
$('#myform').each(function(){
this.reset();
});
I would do like this:
$(document).ready(function() {
$("#createUserButton").on("click", function() {
var form = $("#myForm")[0];
form.reset();
$("input[name=method]").val("CreateUser");
form.submit();
}
});
And your button becomes:
<input type="button" value="Create" class="btn" id="createUserButton">
I'd suggest you to place an id attribute as well in your input text, something like:
<input type="text" name="method" id="methodName" />
And then you could reference it by id which is faster than by name, like this:
$("#methodName").val("CreateUser");
Your code was wrong, in your if you should've used == or === instead of just = and your form should've just have called reset method. No need to iterate over an id using each, even because an ID have to be unique in an HTML page.
Here's a workin fiddle, just type something in the first input to see it happening.
I'd like to find any generic method to change data before sending forms. It is, if I have a <form> that contains a <input> of certain type (class) and user press send button, I'd like to transform this input value to another format so it arrive to server in a corrected format.
I know I can set a submit() handler to process data, but I need a generic solution that setup this mechanism on load on all page forms and forgets about it (perhaps some forms are sent by AJAX, other use Jquery.validate to send, etc)
Use jQuery's to select all form elements: $('form') and register a handler for the form submit event. Something like this:
$('form').submit(function(e){
e.preventDefault()
var $this = $(this)
var formData = $this.serialize()
// do some thing to it
var yourData = transform(formData)
$.ajax({
post: $this.attr('action'),
data: yourData,
...
})
})
References
submit()
jQuery CSS Selector
Form serialize()
Perhaps this
$(document).ready(function() {
$("form").on("submit",function() {
var form = $(this);
var field = form.find("input[name=first_name]");
if (field.length()>0) field.val(field.val().replace("a","b"));
});
});
Yes, why not?
Have an onclick on the form submit button and there you can do whatever you like before you invoke submit(). To add a same function to all input type submit, then iterate over all input elements with the type=buttons and add your onclick handler function to it.
All your forms need to be of the same kind, or if some use input type=submit while others use a button element with your own javascript then you will have to adjust for that.
For submitting the form data to the server from the AJAX call to bind Telerik MVC grid, we can set e.data in OnDataBinding event to a anonymous JavaScript object
<script type="text/javascript">
function Grid_onDataBinding(e) {
var categoryValue = "Beverages";
var priceValue = 3.14;
// pass additional values by setting the "data" field of the event argument
e.data = {
// the key ("category") specifies the variable name of the action method which will contain the specified value
category: categoryValue,
price: priceValue
};
}
</script>
To facilitate the model binding for Boolean, ASP.NET MVC generates checkboxes along with a hidden text field with the same name
<input name="myCheckBox" class="check-box" id="myCheckBox" type="checkbox" CHECKED="checked" value="true"/>
<input name="myCheckBox" type="hidden" value="false"/>
and when these are submitted the data submitted is
myCheckBox=true&MyCheckBox=false - when the checkbox is checked
myCheckBox=false - when the checkbox is not checked
For pages where there is no checkbox, the post data can be easily obtained by
e.data = form.serializeObject()
where serializeObject creates that object by looping thru all the form fields. How to construct that object in case of forms when there are checkboxes as described above? Basically how can a name-value pair list be represented in the object form when the names are allowed to be duplicate?
e.data = {
textBox1: "some value1",
myCheckBox: true //,
//myCheckBox: false // ???
};
The implementation of serializeObject creates an array for such form elements and those are submitted as myCheckBox[]=true&myCheckBox[]=false which breaks the model binding on the server side.
You can select specific form subelements to serialize, rather than just serializing the entire form. This allows you to filter out the ones you don't want:
$('form input:not([type=hidden])').serializeObject();
Edit: Per #amit_g's comment, you want the checkbox when it's checked or the hidden element when it's not. This requires a more complex filter than the :not selector:
$('form input')
.filter(function() {
if ($(this).attr('type') == 'hidden') {
// filter out those with checked checkboxes
var name = $(this).attr('name');
return !$('form input[type=checkbox][name=' + name +']')
.prop('checked');
} else {
// include all other input
return true;
}
})
.serializeObject();
See the working jsFiddle here: http://jsfiddle.net/nrabinowitz/nzmg7/4/
serializeObject uses serializeArray internally and serializeArray serializes only those elements that would be submitted actually. So using the following code, I have disabled the hidden fields corresponding to checkbox and added a change event to toggle the disbaled state on each hidden input. Since the inputs are disabled, they don't get serialized.
The .serializeArray() method uses the standard W3C rules for
successful controls to determine which elements it should include; in
particular the element cannot be disabled and must contain a name
attribute. No submit button value is serialized since the form was not
submitted using a button. Data from file select elements is not
serialized.
$('form.form-class :checkbox').change(function () {
enableDisableCorrespondingHiddenField($(this));
});
$('form.form-class :checkbox').each(function () {
enableDisableCorrespondingHiddenField($(this));
});
enableDisableCorrespondingHiddenField(checkbox) {
$(":hidden[name='" + checkbox.attr("name") + "']", checkbox.parent()).attr("disabled", checkbox.attr("checked"));
}
Unfortunately form.reset() function doesn't reset hidden inputs of the form.
Checked in FF3 and Chromium.
Does any one have an idea how to do the reset for hidden fields as well?
Seems the easiest way of doing that is having <input style="display: none" type="text"/> field instead of <input type="hidden"/> field.
At this case default reset process regularly.
This is correct as per the standard, unfortunately. A bad spec wart IMO. IE provides hidden fields with a resettable defaultValue nonetheless. See this discussion: it's not (alas) going to change in HTML5.
(Luckily, there is rarely any need to reset a form. As a UI feature it's generally frowned upon.)
Since you can't get the original value of the value attribute at all, you would have to duplicate it in another attribute and fetch that. eg.:
<form id="f">
<input type="hidden" name="foo" value="bar" class="value=bar"/>
function resetForm() {
var f= document.getElementById('f');
f.reset();
f.elements.foo.value= Element_getClassValue(f.elements.foo, 'value');
}
function Element_getClassValue(el, classname) {
var prefix= classname+'=';
var classes= el.className.split(/\s+/);
for (var i= classes.length; i-->0;)
if (classes[i].substring(0, prefix.length)===prefix)
return classes[i].substring(prefix.length);
return '';
}
Alternative ways of smuggling that value in might include HTML5 data, another spare attribute like title, an immediately-following <!-- comment --> to read the value from, explicit additional JS information, or extra hidden fields just to hold the default values.
Whatever approach, it would have to clutter up the HTML; it can't be created by script at document ready time because some browsers will have already overridden the field's value with a remembered value (from a reload or back button press) by that time that code executes.
Another answer, in case anyone comes here looking for one.
Serialize the form after the page loads and use those values to reset the hidden fields later:
var serializedForm = $('#myForm').serialize();
Then, to reset the form:
function fullReset(){
$('#myForm').reset(); // resets everything except hidden fields
var formFields = decodeURIComponent(serializedForm).split('&'); //split up the serialized form into variable pairs
//put it into an associative array
var splitFields = new Array();
for(i in formFields){
vals= formFields[i].split('=');
splitFields[vals[0]] = vals[1];
}
$('#myForm').find('input[type=hidden]').each(function(){
this.value = splitFields[this.name];
});
}
You can use jQuery - this will empty hidden fields:
$('form').on('reset', function() {
$("input[type='hidden']", $(this)).val('');
});
Tip: just make sure you're not resetting csrf token field or anything else that shouldn't be emptied. You can narrow down element's specification if needed.
If you want to reset the field to a default value you can use(not tested):
$('form').on('reset', function() {
$("input[type='hidden']", $(this)).each(function() {
var $t = $(this);
$t.val($t.data('defaultvalue'));
});
});
and save the default value in the data-defaultvalue="Something" property.
I found it easier to just set a default value when the document is loaded then trap the reset and reset the hidden puppies back to their original value. For example,
//fix form reset (hidden fields don't get reset - this will fix that pain in the arse issue)
$( document ).ready(function() {
$("#myForm").find("input:hidden").each(function() {
$(this).data("myDefaultValue", $(this).val());
});
$("#myForm").off("reset.myarse");
$("#myForm").on("reset.myarse", function() {
var myDefaultValue = $(this).data("myDefaultValue");
if (myDefaultValue != null) {
$(this).val(myDefaultValue);
}
});
}
Hope this helps someone out :)
$('#form :reset').on('click',function(e)({
e.preventDefault();
e.stopImmediatePropagation();
$("#form input:hidden,#form :text,#form textarea").val('');
});
For select, checkbox, radio, it's better you know (hold) the default values and in that event handler, you set them to their default values.
Create a button and add JavaScript to the onClick event which clears the fields.
That said, I'm curious why you want to reset these fields. Usually, they contain internal data. If I would clear them in my code, the post of the form would fail (for example after the user has entered the new data and tries to submit the form).
[EDIT] I misunderstood your question. If you're worried that someone might tamper with the values in the hidden fields, then there is no way to reset them. For example, you can call reset() on the form but not on a field in the form.
You could think that you could save the values in a JavaScript file and use that to reset the values but when a user can tamper with the hidden fields, he can tamper with the JavaScript as well.
So from a security point of view, if you need to reset hidden fields, then avoid them in the first place and save the information in the session on the server.
How I would do it is put an event listener on the change event of the hidden field. In that listener function you could save the initial value to the DOM element storage (mootools, jquery) and then listen to the reset event of the form to restore the initial values stored in the hidden form field storage.
This will do:
$("#form input:hidden").val('').trigger('change');
You can reset hidden input field value using below line, you just need to change your form id instead of frmForm.
$("#frmForm input:hidden").val(' ');
I have some javascript which catches changes to a form then calls the form's regular submit function. The form is a GET form (for a search) and i have lots of empty attributes come through in the params. What i'd like to do is to delete any empty attributes before submitting, to get a cleaner url: for example, if someone changes the 'subject' select to 'english' i want their search url to be
http://localhost:3000/quizzes?subject=English
rather than
http://localhost:3000/quizzes?term=&subject=English&topic=&age_group_id=&difficulty_id=&made_by=&order=&style=
as it is at the moment. This is just purely for the purpose of having a cleaner and more meaningful url to link to and for people's bookmarks etc. So, what i need is something along these lines, but this isn't right as i'm not editing the actual form but a js object made from the form's params:
quizSearchForm = jQuery("#searchForm");
formParams = quizSearchForm.serializeArray();
//remove any empty fields from the form params before submitting, for a cleaner url
//this won't work as we're not changing the form, just an object made from it.
for (i in formParams) {
if (formParams[i] === null || formParams[i] === "") {
delete formParams[i];
}
}
//submit the form
I think i'm close with this, but i'm missing the step of how to edit the actual form's attributes rather than make another object and edit that.
grateful for any advice - max
EDIT - SOLVED - thanks to the many people who posted about this. Here's what i have, which seems to work perfectly.
function submitSearchForm(){
quizSearchForm = jQuery("#searchForm");
//disable empty fields so they don't clutter up the url
quizSearchForm.find(':input[value=""]').attr('disabled', true);
quizSearchForm.submit();
}
The inputs with attribute disabled set to true won't be submitted with the form. So in one jQuery line:
$(':input[value=""]').attr('disabled', true);
$('form#searchForm').submit(function() {
$(':input', this).each(function() {
this.disabled = !($(this).val());
});
});
You can't do it that way if you call the form's submit method; that will submit the entire form, not the array you've had jQuery create for you.
What you can do is disable the form fields that are empty prior to submitting the form; disabled fields are omitted from form submission. So walk through the form's elements and for each one that's empty, disable it, and then call the submit method on the form. (If its target is another window, you'll then want to go back and re-enable the fields. If its target is the current window, it doesn't matter, the page will be replaced anyway.)
Well one thing you could do would be to disable the empty inputs before calling "serializeArray"
$('#searchForm').find('input, textarea, select').each(function(_, inp) {
if ($(inp).val() === '' || $(inp).val() === null)
inp.disabled = true;
}
});
The "serializeArray()" routine will not include those in its results. Now, you may need to go back and re-enable those if the form post is not going to result in a completely refreshed page.
Maybe some of the proposed solutions worked at the moment the question was made (March 2010) but today, August 2014, the solution of disabling empty inputs is just not working. The disabled fields are sended too in my Google Chrome. However, I tried removing the "name" attribute and it worked fine!
$('form').submit(function(){
$(this).find('input[name], select[name]').each(function(){
if (!$(this).val()){
$(this).removeAttr('name');
}
});
});
Update:
Ok, probably the reason because disabling fields doesn't worked to me is not that something changed since 2010. But still not working in my Google Chrome. I don't know, maybe is just in the linux version. Anyway, I think that removing the name attr is better since, despite what policy takes the browser about disabled fields, there is no way to send the parameters if the name attr is missing. Another advantage is that usually disabling fields implies some style changes, and is not nice to see a style change in the form a second before the form is finally submited.
There is also a drawback, as Max Williams mentioned in the comments, since the remove name attr solution is not toggleable. Here is a way to avoid this problem:
$('form').submit(function(){
$(this).find('input[name], select[name]').each(function(){
if (!$(this).val()){
$(this).data('name', $(this).attr('name'));
$(this).removeAttr('name');
}
});
});
function recoverNames(){
$(this).find('input[name], select[name]').each(function(){
if ($(this).data('name')){
$(this).attr('name', $(this).data('name'));
}
});
}
However, I think this is not a very common case since we are submitting the form so it is assumed that there is no need to recover the missing name attrs.
Your problem helped me figure out my situation, which is a bit different - so maybe someone else can benefit from it. Instead of directly submitting a form, I needed to prevent empty form elements from being collected into a serialized array which is then posted via AJAX.
In my case, I simply needed to loop through the form elements and disable all that were empty, and then collect the leftovers into an array like so:
// Loop through empty fields and disable them to prevent inclusion in array
$('#OptionB input, select').each(function(){
if($(this).val()==''){
$(this).attr('disabled', true);
}
});
// Collect active fields into array to submit
var updateData = $('#OptionB input, select').serializeArray();
Or serialize, clear empty key=value pairs with regex and call window.location:
$("#form").submit( function(e){
e.preventDefault();
//convert form to query string, i.e. a=1&b=&c=, then cleanup with regex
var q = $(this).serialize().replace(/&?[\w\-\d_]+=&|&?[\w\-\d_]+=$/gi,""),
url = this.getAttribute('action')+ (q.length > 0 ? "?"+q : "");
window.location.href = url;
});
Another approach I always recommend is to do that on server side, so you are able to:
Validate the input data correctly
Set default values
Change input values if needed
Have a clean URL or a friendly URL such as "/quizzes/english/level-1/"
Otherwise you will have to deal with text input, select, radio etc...