Develop Reference

Passing Variables to Bootstrap Modal and Passing Them BACK

The variable data passed to a Bootstrap modal is hard coded in HTML data-text element field using "data-text" (according to the Bootstrap examples). If the modal's purpose is to allow a user to change that, then how do I send that back to the raw HTML data-text to update it for next time?
JS newbie here. I got Bootstrap 4 modals working and updating back to the server by Ajax (with a lot of Googling of StackOverFlow thanks!). I have about 100 text elements on the page which all load the same modal for editing of the clicked text field. The field initial value is hard coded into the page HTML in the data-text field (following the Bootstrap modal example). This allows passing of the current text value to pre-populate the modal field with the existing text value for editing.
Next, the user edits the note field in the modal and clicks submit. I am able to get the value and pass it back to the server, and update the DOM with the new edited value on the page, and everything works and looks great! So far so good.
Now here's the problem. Since I have not been able to figure out how to change the data-text field (which is hard coded in the page HTML), the screen (DOM) updates with the new value after submit correctly, but the data-text field of the element does not update. It is still the old value. It means the NEXT time I click to edit the text, the OLD value of the text field is pre-populated in the modal for editing.
Question: how do I update html data-text field by JS?
I have researched this problem at great length and without Stack Overflow I would never be able to get it working, so much appreciate you guys. Dozens of questions about passing variable TO Modals, but very few about passing the data back, and NONE about setting data-text on submit by JS.
text element definition example. This is a slightly simplified example. The text field contains some data from the server database, HTML is generated by PHP/MySQL. (1 out of 100 elements on page):
<td id="note_12345678" data-toggle="modal" data-target="#noteModal" data-note="<some text from db>" class="note"><same text from server db></td>
Here is the JS on submit code. Everything works except for the last line where I am trying to change the "data-note" field of the element:
function note_submit(element) {
var note = document.getElementById('message-text').value;
ajaxcall("/ajaxclick.php" , { note:note } , null); // Simplified, all is working.
noteElement = document.getElementById('note_12345678');
noteElement.innerText = note ; // Updates the DOM with submitted note.
noteElement.data-note = note ; // <== trying to change data-note here but obviously a syntax error.
}
Everything is working fine up to that last step. Clicking the text field opens modal, pre-loads the text for editing, allows the user to edit, click submit sends to server by Ajax for update, DOM note on screen is updated by JS. if I RELOAD the page, it loads the new edited text value from server db. Everything working great. Lots of joy.
Problem is NEXT time I click on the text element to edit it, the modal loads the OLD value from data-note hard coded into HTML. How to update it upon submit by JS? Thanks a million for any assistance. So close.
Updated: page is loading jquery-3.3.1.js, and bootstrap/4.0.0/js/bootstrap.min.js. Browser is FF V66.

Dependable textbox autocomplete method

page imageThis Images shows my page where i am facing a problem, i want my 'company' textbox get autocomplete by value fetched from database when i input a value in 'code'.
in a seperate page mysql queries will run to get company where code='*'
Both 'code' and 'company' are present in my databasedatabase image
Tried lots of techniques but failed to achieve anything.
Please help!!

Give us some code please.
You want to submit form and then, on new page - enter a value to new form with second textbox?
As you probably know - if you want to get data from database you must use classic SQL query in PHP file.
But - if you want do dynamicaly autocomplete second textbox without submit - you can use jQuery:
$('#your_textbox').on('input', function() {
/* This will be fired every time, when textbox's value changes. */
$('#your_second_textbox').val($('#yout_textbox').val(''));
} );

Add items to dropdownlist with javascript and persist in postback

I'm pretty new to web development, and I've encountered the following problem I don't really understand. Working in VS2010 with visual basic.
I have a page (aspx), which has a gridview, and this has a few columns, including a column with tickboxes and a column 'action', which has an empty, hidden dropdownlist to begin with (every row has this).
Whenever a user ticks a box, I retrieve some values from the server with an AJAX-call (which is my first attempt at AJAX :-)) and with those values I populate a dropdownlist in the 'action' colum of the selected row. So far so good.
The user can then make a selection on the dropdownlist, en then he presses a button (upload), and a postback is done to process the information.
However, in the code behind, I can't retrieve the added items in the dropdownlist (let alone the selected value). I CAN retrieve the dropdownlist, but it has no items.
After googling for some time I realised that client-side changes are not persisted when the form is posted to the server, which I understand- but it also seems odd. The dropdown is created when the page is created, so why doesn't it store the javascipt-added items? Especially since a few work-arounds I found use a hiddenfield to store the added items or selectedvalue. If I can store them in a hiddenfield, why can't I store them in the actual dropdownlist?
I'm obviously not understanding how websites work... But this means that, after a page is initially loaded, you can change values in dropdowns and listboxes and such, but these will never be available serverside?
Edit: some code; the first a javascript-snippet how I add the different values I retrieved through the AJAX call:
var drop = row.findElement("ddlAction"); //find the dropdownelement in the DOM
for (j = 0; j < dropdownitems.length; j++) { //add all the options from xml
option = document.createElement("option");
option.text = dropdownitems[i].getAttribute("text");
option.value = dropdownitems[i].getAttribute("value");
drop.add(option, null);
}
This works fine, the dropdownlist is filled and I can select. But when the page gets posted I do the following in the server code:
Dim SelCount As Integer = LocalFilesGrid.SelectedItems.Count
If SelCount >= 0 Then
For Each dataItem In LocalFilesGrid.SelectedItems
Dim drop As DropDownList
drop = dataItem.FindControl("ddlAction")
If drop.Items.Count = 0 Then 'always zero
MsgBox("Nope")
End If
Next
End If
I'd like to be able to loop through the selected rows of the grid, get the corresponding dropdownlist and selectedvalue.

When you mix such different technologies you will end up in troubles like this. What you are trying to do is bit of Ajax and a bit of ASP.NET. Choose one and then use it. If you choose ASP.NET instead of AJAX call use UpdatePanel which will simplify your life.
If you want to Ajax stuff your self, then handle the button click and submit the request by ajax rather than postback.
The reason why you are able to retrieve the drop down but not the items because you must have declared the drop down in aspx but the items were added on client side, so server has no knowledge about the items.
The reason is ASP.NET uses view state and you can not mess with view state. So you can add the data to hidden field and read them at server but you can not write the data in view state.
The best way is use ASP.NET with UpdatePanels. If you mix, then you will have to keep doing some sort of trick at every step. If you want to do your own Ajax stuff better use MVC and Razor(not mvc with aspx) because it is made for such use.

add new option to select drop down list using jsp

can anyone please suggest , how to add new option to drop down list (using select tag in html) so that user can enter the new value and on submit it should be appended to the existing list ..i am able to populate it's option list via DB dynamically and it's working properly
i am having 5 drop down mutually exclusive category lists in a single table row and i am providing them some initial options.Now i want that if the list contains user's required option then user can select from existing one ...else it should be able to add a new entry to that list & it should be simultaneously updated in DB on submit.

Follow this steps
As you are populating the drop down from databse . So its better to add the value in database only.
I think your user will be entering the value in a text box. So on submit call a method or servlet which can be used to add the value in the database field from which you are populating the drop down.
After updation make your servlet to return on the same page.
Now you can see your new option in the drop down.
Update on further problem explaination
For your problem do one thing
Give a text box in last option of each dropdown.
Select an event in which after the new value entered by user in that text box an java script function can be triggered line onmouseout.
In that function call get the text value .
Now call your servlet or method or whatever you are using to update the db with value value in the column corresponding to that drop down using Ajax or normally.
Refresh the page.

hiii,
finally it's done.
i used following function as-
function abc()
{
var myoption = document.createElement("option"); //works with both mozilla and IE
myoption.text ="mytext";
myoption.id="mytext";
myoption.name="mytext";
myoption.value ="mytext"; //Probably, the sID stuff
document.getElementById("drop_1").options.add(myoption);
}
& so on within loop.
thanks to all .

Grails: How to display data from datasource based on selection in GSP form

I have a pulldown menu generated from a MySQL dataSource.
<g:select onchange="selected()" id="name" name="name" from="${listOfNames()}" noSelection="['':'--']"/>
this populates the menu with one column from my table
Now based on the selection I want to display additional columns from the same table as text on the gsp form.
so user selects Name1 from dropdown. I display underneath the dropdown menu
Name1. age 21. degree yes.
I have an action inside my controller called allDetails that queries all values associate with a name and returns it a string. But I am not sure how to pass it parameters
"${remoteFunction(action:'allDetails', params: \'name=\' params.name')}
What is the best way to do this. run a JavaScript remote function inside selected() or a gsp tag that calls the action somehow? how to then display the returned string? Change the innerHTML?
tried http://www.grails.org/AJAX-Driven+SELECTs+in+GSP

You cannot use remoteFunction or other core Grails tags, because its text is fully generated during page rendering, and you only know the selected name during Javascript executing in onchange.
So use jQuery Ajax call (unless you switched to a different Javascript plugin).
And I suggest that you select not a name, but an id of that person, like in a second g:select example.