Develop Reference

How to pass a value from a Javascript generated button to a controller?

My code generates a table with a button at the end of each row. When the user clicks a button how can I pass a property u.userEmail to the controller via the button? Will the value being sent to the controller be a string?
My (non-working) attempt:
<script>
$(document.body).append("waiting on async table to load<br>");
$(document).ready(function () {
$.getJSON("/Account/LoadClaimsTable", function (crewResponse) {
//returns a List<UserClaims>
$(document.body).append("<table>")
crewResponse.forEach(function (u) {
var s = "";
s+="<tr><td>" + u.userEmail + "</td>";
u.userClaims.forEach(function (k) {
console.log("added claim"+k.value);
s += ("<td>" + k.type + "</td><td>" + k.value + "</td><td>" +
"<input type=\"hidden\" name=\"userEmail\" value=\"`${u.userEmail}`\" />"+
"<input type=\"button\" value=\"Create\" onclick=\"location.href='#Url.Action("EditClaims", "Account")'" />
+"</td>");
});
s += "</tr>";
$(document.body).append(s);
s = "";
});
$(document.body).append("</table>")
});
});
</script>
AccountController.cs contains:
public ActionResult EditClaims(string userEmail)
{
return View("StringView", userEmail);
}

You have to pass it on the url of the action. Not sure if you want to pass u.userEmail, but it could looks like this:
crewResponse.forEach(function (u) {
var s = "<tr><td>" + u.userEmail + "</td>";
u.userClaims.forEach(function (k) {
console.log("added claim"+k.value);
s += ("<td>" + k.type + "</td><td>" + k.value + "</td><td>" +
"<input type=\"hidden\" name=\"userEmail\" value=\"`${u.userEmail}`\" />"+
"<input type=\"button\" value=\"Create\" onclick=\"location.href='#Url.Action("EditClaims", "Account")?userEmail=" + u.userEmail + "'\"/></td>");
});
s += "</tr>";
$(document.body).append(s);
});

There are multiple ways to do it. One is mentioned in the answer above by Felipe. Here is another alternate approach using unobtrusive js
Add the email as html5 data attributes to the button along with another attribute which we will use bind the click behavior.
u.userClaims.forEach(function (k) {
// Add quotes as needed if you want multiline ( i just removed those)
s += "<td>" + k.type + "</td><td>" + k.value + "</td><td>
<input type='button'
clickablebutton data-email='" + u.email + "' value='Create'/></td>";
});
Now, in your document ready, bind a click event handler to those elements (with our custom attribute) and read the data attribute and build the url you need.
$(document).on("click", "input[clickablebutton]", function (e){
var url = '#Url.Action("EditClaims", "Accounts")?useremail=' + $(this).data("email");
window.location.href = url;
});
Some other suggestions
Use the appropriate element. Button is better than input (Consider accessibility)
If it is for navigation, Use an anchor tag instead of a button.
Inline javascript is not great. Let the browser parses your markup without any interruptions and you can add the behavior scripts later (that is the whole point of uobutrisive js approach)

The approach you appear to be taking would be Ajax, response, render a template. With that being said, you may want to rethink your approach.
Step 1.
Build a template
<template id="...">
<button type="button" value="[action]" onclick="[url]">[text]</button>
</template>
Step 2.
Create your request.
axios.get('...').then((response) => {
// Retrieve template.
// Replace bracket with response object model data.
html += template.replace('[action]', response.action);
});
Step 3.
Have the JavaScript render your template.
The above can create a clear concise codebase that is easier to maintain and scale as the scope changes, rather than an individual request performing a change with embedded markup. This approach has worked quite well for me, also I feel it'll make you troubleshooting and definition easier, as the controller is handing an object back to your JavaScript instead of a markup / view data. Which will be a better finite control for the frontend and clear modifications in future.

Getting variable into JS via PHP assigned id

I have the following Javascript to generate a silent call to another sheet to update a database value without refreshing the page
function UpdateDB(table,column,type){
var value = $("#Assigned").val();
$.post("UpdateValuation.php?Table=" + table + "&Value=" + value + "&Column=" + column + "&Type=" + type, {}).done();
};
This works perfectly but only for the "Assigned" table row since it is statically assigned.
I use the following php to generate the table entry with button
print "<tr><td>" . $stuff['Status'] . "</td><td ><input type=\"text\" id=\"" . $stuff['Status'] . "\" name=\"" . $stuff['Status'] . "\" value=". $stuff['Value'] ." size = \"4\" style = \"text-align: center\"/><button onclick=\"UpdateDB('NOCstatus','Status','". $stuff['Status'] ."');\">Update</button></td></tr>";
Which after variables are assigned looks like this for my "Pending" row
<input id="Pending" type="text" style="text-align: center" size="4" value="120" name="Pending"> </input>
<button onclick="UpdateDB('NOCstatus','Status','Pending');">
Update
</button>
My problem is that passing "this.value" or trying to use a variable in the javascript portion I always come up with a blank value, the only time I can get a value to be correct is by statically assigning the "#Assigned" or "#Pending" in the value field. I have hundreds of entries so I don't want to write the function over for each of these. I know there is probably something extremely simple I am missing but I cannot get the pieces to fit.
I need to pass the typed in value in the input field to the function to update the database. Please help.

function UpdateDB(table,column,type){
var value = $('#'+type).val();
$.post("UpdateValuation.php?Table=" + table + "&Value=" + value + "&Column=" + column + "&Type=" + type, {}).done();
};
?

JQuery click event firing multiple times

I know that there's lot here on already on multiple click events being fired off, I think I've read them all but still can't see what's going wrong here.
Hope fully I'm missing something obvious that someone else can pick up easily...
Some background
My code works inside an Enterprise Social Networking platform and creates a BI dashboard for content analysis (about a 1000 lines of the stuff, mostly domain specific, so too much to post in it's entirety).
The part that is causing me grief is the function that builds the dashboard visualisation itself.
Here goes...
function makePage(){
$("#policyCount").text(policyCount);
var docTypes=getGlobalDocTypes(polOwners); //returns a constrained vocab array
var statusTypes=getGlobalStatusTypes(polOwners); //returns a constrained vocab array
$.each(polOwners,function(){ // polOwners is a global array that contains the BI data to be visualised
html=""
var ownerName = this.name.split(":")[1]; // name is a str in format "Owner:HR"
html += "<div id='" + ownerName + "' class='ownerData'>";
html += "<div class='ownerHeading'>" + ownerName + "</div>";
html += this.policies.length + " Policy documents maintained<br />"; // policies is an array of docs managed by owner
divIDReview = "dboard_" + ownerName + "reviewchart";
html += "<div id='" + divIDReview + "' class='dboardelement'></div>";
divIDType = "dboard_" + ownerName + "typechart";
html += "<div id='" + divIDType + "' class='dboardelement'></div>";
divIDStatus = "dboard_" + ownerName + "statuschart";
html += "<div id='" + divIDStatus + "' class='dboardelement'></div>";
html += "<div id='" + ownerName + "ToggleTable' class='toggletable' owner='" + ownerName + "'>";
html += "Click to display all " + ownerName + " documents<br /></div>";
html += "<div id='" + ownerName + "polTable' class='poltable'>";
html += getPolTable(this.policies); // Returns an HTML table of doc metadata
html += "</div>";
html += "</div>";
  $("#owners").append(html); // When this function is called #owners is an empty div
$(".toggletable").mouseover(function(){
$(this).css({'cursor':'pointer','text-decoration':'underline'});
});
$(".toggletable").mouseout(function(){
$(this).css( {'cursor':'default','text-decoration':'none'});
});
$(".toggletable").each(function(i, elem){
$(elem).click(function(){
if ($(this).next(".poltable").css("display")=="none"){
// Currently hidden - so show
if (debug){console.log($(this).attr("id") + " was clicked")}
$(this).html("Click to hide " + $(this).attr('owner') + " documents<br/>");
$(this).next(".poltable").css("display","block");
} else {
if (debug){console.log($(this).attr("id") + " was clicked")}
$(this).html("Click to display all " + $(this).attr('owner') + " documents<br />");
$(this).next(".poltable").css("display","none");
}
});
});
// the next section calls functions that use the Google vis api to draw pie charts
drawPie(300,200, "Review Status", "Status", "Policies", getReviewStatus(this.policies), ["green","orange","red"], divIDReview);
drawPie(300,200, "Document Types", "Type", "Docs", getDocTypes(this.policies, docTypes), [], divIDType);
drawPie(300,200, "Document Status", "Status", "Docs", getStatusTypes(this.policies, statusTypes), [], divIDStatus);
});
}
Hopefully that's enough to illustrate the problem.
You'll see that the code builds a dashboard display for each polOwner consisting of three pie charts and an option to hide or display a table of underlying data.
I started by applying the click event to the .toggletable class. When that fired multiple times I used the method described on another answer here with the .each to attach a unique event to each instance of the class.
So, what happens?
There are currently 9 polOwners and at first glance, the click event only seems to be toggling the display state of every other table. The console log however shows that this is because it is firing 9 times for the first instance, 8 for the second, 7 for the third etc. with the odd numbers leaving the table in the alternate state (when this works the display will change to a .toggle animation).
For info, While I'm a text editor person, I do have a copy of MS Expression Web 4 which is a useful tool for error checking HTML. I've pasted in a copy of the entire generated markup (nearly 4000 lines) and can't see any bad nesting or structure errors.
Any ideas folks?

You've got some nested loops:
// jQuery each on polOwners
$.each(polOwners,function(){
// ... code that appends .toggletable class
// jQuery each on .toggletable class
$(".toggletable").each(function(i, elem){
// code that runs on the toggletable element
});
});
For each polOwner you are adding a div with the toggletable class. Then inside there you are looping through each div with a toggletable class and adding a click event.
This adds 1 click for the first polOwner, 2 for the second, three for the third and so on.
Move the toggletable each outside of the polOwner each and you should be good

jquery: "Exception thrown and not caught" in IE8, but works in other browsers

My code works fine in other browsers, but in IE8 I get "error on page" - and when I click that it says:
"Exception thrown and not caught Line: 16 Char: 15120 Code: 0
URI: http://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.min.js"
I tried linking to jquery.js (rather than jquery.min.js) and to 1.5.1/jquery.min.js,
but problem still remains.
Can someone correct/improve my code for me, or guide me as to where to look. Thanks
<script type="text/javascript">
function fbFetch()
{
var token = "<<tag_removed>>&expires_in=0";
//Set Url of JSON data from the facebook graph api. make sure callback is set with a '?' to overcome the cross domain problems with JSON
var url = "https://graph.facebook.com/<<ID_REMOVED>>?&callback=?&access_token=" + token;
//Use jQuery getJSON method to fetch the data from the url and then create our unordered list with the relevant data.
$.getJSON(url, function(json)
{
json.data = json.data.reverse(); // need to reverse it as FB outputs it as earliest last!
var html = "<div class='facebook'>";
//loop through and within data array's retrieve the message variable.
$.each(json.data, function(i, fb)
{
html += "<div class='n' >" + fb.name;
html += "<div class='t'>" + (dateFormat(fb.start_time, "ddd, mmm dS, yyyy")) + " at " + (dateFormat(fb.start_time, "h:MMtt")) + "</div >";
html += "<div class='l'>" + fb.location + "</div >";
html += '<div class="i"><a target="_blank" title="opens in NEW window" href="https://www.facebook.com/pages/<<id_removed>>#!/event.php?eid=' + fb.id + '" >more info...</a></div>';
html += "</div >";
}
);
html += "</div>";
//A little animation once fetched
$('.facebookfeed').animate({opacity: 0}, 500, function(){
$('.facebookfeed').html(html);
});
$('.facebookfeed').animate({opacity: 1}, 500);
});
};

Does the code do the job in IE8 or does it break? The reason I ask is because if it works as expected you could just wrap it in a try{ } catch{ \\do nothing } block and put it down to another thing IE is rubbish at.
You may be better off creating an object for the creation of the facebook div. Something like...
var html = $('<div />');
html.attr('class', 'facebook');
Then in your each loop you can do this...
$('<div />').attr('class', 'n').append(fb.name).appendTo(html);
$('<div />').attr('class', 't').append etc...
Then append html to the facebookfeed object
Doing this may remove the scope for error when using single quotes and double quotes when joining strings together, which in turn may solve your issue in IE8
$('.facebookfeed').fadeOut(500, function(){
$(this).append(html).fadeIn(500);
});
Hope this helps!
UPDATE
The append method is used to add stuff to a jquery object. For more info see here
So to surround the div's as you mentioned in the comments you would do something like this...
var nDiv = $('<div />').attr('class', 'n').append(fb.name);
$('<div />').attr('class', 't').append(fb.somethingElse).appendTo(nDiv);
// etc
And then you would need to append that to the html div like so...
html.append(nDiv);
So that would give you
<div class="facebook">
<div class="n">
value of fb.name
<div class="t">
value of fb.somethingElse
</div>
</div>
</div>
So what you have done is created a new jquery object and appended to that, then appended that to the html object which you have then appended to the facebookfeed div. Confusing huh?!

using .append to build a complex menu

To build a menu block which should be switchable with hide/unhide of the menu items, I'm using .append html.
The code idea is this:
navigat += '<h3 class="infoH3"> <a id="' + menuID +'"'
+ ' href="javascript:slideMenu(\'' + menuSlider + '\');">'
+ menuName + '</a></h3>';
navigat += '<div id="' + menuSlider + '" style="display:none">';
navigat += ' <ul>';
navigat += ' <li>aMenu1</li>'
navigat += ' <li>aMenu2</li>'
navigat += ' <li>aMenu3</li>'
navigat += ' </ul>';
navigat += '<!-- menuName Slider --></div>';
$("#someElement").append (navigat);
This is doing well .. so far.
But the point is::
I use JS to read the required menu items (eg. 'aMenu1' together with title and/or link info) from a file to build all that, eg. for 'aMenu1' a complex is composed and $("#someElement").append(someString) is used to add that the 'someElement'.
At the moment I build those html elements line by line. Also OK .. as far as the resulting string has the opening and closing tag, eg. "<li>aMenu2</li>".
As can be seen from above posted code there is a line "<div id="' + menuSlider + '" style="display:none">".
Appending that -- AFAIS -- the .append is automatically (????) adding "</div>" which closes the statement.
That breaks my idea of the whole concept! The menu part isn't included in the 'menuSlider '.
QQ: How to change it -- NOT to have that "</div" added to it??
Günter

You could change you method around to use document fragment style creation and an object to populate the properties on the elements, like this:
var someElement = $("#someElement");
$('<h3 class="infoH3"></h3>').append($('<a />',
{ 'id': menuID,
'href': '#',
click: function() { slideMenu(menuSlider); }
})
).appendTo(someElement);
var div = $('<div />', { 'id': menuSlider, css: {display: 'none'} });
$('<ul />').append('<li>aMenu1</li>')
.append('<li>aMenu2</li>')
.append('<li>aMenu3</li>')
.appendTo(div);
div.appendTo(someElement);
This is a very different way of doing it, first we're caching the $("#someElement") object so we're not searching for it repeatedly. Then we're creating the <h3> as an object, putting the link inside, then inserting then appending the whole thing to someElement. In the last, the same approach it's creating the <div>, setting it's properties, then creates the <ul> menu and appends it inside...then appends that whole div to someElement as well.
As a side note, I'm not sure how .slideMenu() works, but an event handler that works via $(this).parent().next() (or give the div a class) would work as well, and you wouldn't need a function with the slider argument passed.