I am looking to script a site that has a set of changing values. I am trying to figure out how to call the text value inside of only one of these entries at a time.
Any one of these can look like this
<tr ng-repeat="(key, game) in crash.games.slice().reverse()" class="" style="">
<td ng-if="::game.crash > 199" class="crashHighResult">RANDOM NUMBER THAT I WANT TO SEE</td>
tr is the parent of td and the text value inside of td is what I'm trying to see
The only problem I'm experiencing is that there are as many as 20 entries stored during this time and they can all have seemingly the same classes and parents as every other one, the only difference being the random number value...
I am thinking that If I can pull them all at the same time and then maybe create an array with those values I might be able to do what I need to do but I'm a bit stumped.
I am very new to javascript and jquery and this is a learning experience for me. Thanks for your help!
Your best bet would be to use document.querySelectorAll if you want to understand some native JS techniques. There are a couple of other ways of getting the elements you want (getElementsByClassName and getElementsByTagName) but they don't play nearly as well with forEach as does the former.
So, to grab the elements:
let cells = document.querySelectorAll('td');
And to loop over that nodelist:
cells.forEach(function (cell) {
console.log(cell.textContent);
});
At the moment the code just logs the text content (your random number) to the console, but you can get a feel for what you can now do with that data.
For example, to get the last (most recent?) random number (the last cell in the nodelist) you would use:
let rnd = cells[cells.length - 1].textContent;
Hope this helps you out.
If you need to select the first tr td in the table to get the value, using jQuery you can select all tr td elements and then specify the first one.
$("tr td").first().text();
This selector finds all tr td elements as it traverses the dom, so it will find the top row in the table first. The first() function returns a jquery object of the first element found. The text() gets whatever text is inside the td tags, basically the same as the js innertext or textcontent.
If you want to do processing with all the values you can use the jquery selector each() function.
$("tr td").each(function (index , element) {console.log($(element).text())})
This loops through all the elements and prints their values to the console, but you could modify the function to sum the values, put them in an array, or whatever.
Related
I'm attempting to target the last parent table row within a table that has children table-row elements inside of it. I've tried the below jQuery to target the :last pseudo, however, like expected, it is targeting the absolute last table-row element within the targets parent table.
$('table[id*="dgRegistrantList"]').find('tr:last').addClass('EventRegLastAttendee')
I've put together a jsFiddle with the HTML block I'm attempting to target with the jQuery, I hope it is helpful!
http://jsfiddle.net/jodriscoll/LZA7e/
The Green table-row is the one I would like to target, however, the one highlighted in Red is the obvious one receiving the class.
This system can generate a variant of table rows depending on the users selection prior to this "Step". For a full example of what I'm working with, visit: http://secure.massgeneral.org/event-form (I'm working with Step 2).
Please be aware that the HTML I'm working with is produced by a CMS software that I as the customer, do not have access to changing. Hence the purpose of this jQuery exercise.
If all the parent <tr> elements have the classes BBListOddRowStyle or BBListEvenRowStyle you can do this:
$('table[id*="dgRegistrantList"]').find('tr[class*=RowStyle]:last')
.addClass('EventRegLastAttendee')
DEMO
If not, you can use .children() twice to make sure you target the right ones:
$('table[id*="dgRegistrantList"]').children('tbody')
.children('tr:last').addClass('EventRegLastAttendee')
DEMO
Use this code to target the last row:
$('table[id*="dgRegistrantList"]').find('tr[class^=BBList][class$=RowStyle]:last').addClass('EventRegLastAttendee')
Explanation:
tr //it will look for tr
[class^=BBList] //which class starts with BBList
[class$=RowStyle] //and ends with RowStyle (so we're leaving Odd and Even inside and not recognized)
:last //the last of those element, if you remove it you select all of them
Is .children() what you're looking to do?
$('table[id*="dgRegistrantList"]').children('tr:last').addClass('EventRegLastAttendee');
.children() only goes down one dom level, while .find() will go down as far as it can.
Don't use find. It will look at any depth and it may match unintended subtables. Perhaps it will work for your example, but you don't want to be acquiring a bad habit. Plus, find will be more costly than a targeted approach.
You want a more targeted approach:
var targetTd = $('table[id*="dgRegistrantList"]').children('tbody').children('tr:last').find('table:first').children('tbody').children('td:last');
use this code to target parent tr last row
$('table[id*="dgRegistrantList"]').find('tr[class^=BBList]:last').addClass('EventRegLastAttendee');
I want to backup an html table to afterwards filter it using jquery:
$('.row').closest('td').not(':contains(' + v + ')').parent('tr').remove();
Since I do remove() I have to back up the rows before:
var allTable = $('#mytable').html();
And then, when filter is performed I turn back to previous table data:
$('#mytable').html($(allTable));
But this does not work. If I do:
alert($(allTable).filter('tr').length);
next to the first assignment, zero rows are returned.
Please, can you assist me?
filter() is used to find elements within an array of elements. This isn't what you need. You're looking to find() the child elements within another. Also, storing the HTML only to turn it back in to a jQuery object is a little redundant - you may as well just store the jQuery object itself. Try this:
var $table = $('#mytable');
$table.remove(); // use your existing logic here
alert($table.find('tr').length);
$table.appendTo('body'); // add the table back in to the DOM when conditions are met
Example fiddle
I ran into a similar issue when using a highlight function. I solved it by cloning the table into a hidden div and restoring it from there, instead of from a variable. see jquery highlight() breaking in dynamic table
Did you solve this problem?
I suggest a workaround.
Instead of using your cloned table, make a (temporary) copy of it and use it for alert.
var alertTable = allTable;
alert($(alertTable).filter('tr').length);
I have a rather big table where I dynamically remove some rows. It works, but it is very slow. Right now it takes approx. 1.5 seconds to remove 50 rows on IE8 and Firefox (almost no difference between the browsers).
I know that DOM manipulation is slow in general, but there must be a faster way to do this.
Right now, I'm using this syntax:
$("#myTable tr").slice(250, 300).remove();
The offsets in the slice() method may vary. I use slice() since this was recommended in jQuerys help and other methods to perform the same thing - like find() or eq() - where not faster. I read about doing an empty() before the removal, but that was even slower.
Consider using the actual javascript, in case jQuery is triggering render refreshes: http://jsfiddle.net/MbXX5/
var removeRows = function(ofTable,from,to) {
for(var row=to; row>=from; --row) {
ofTable.deleteRow(row);
}
};
As you can see in the jsfiddle, this is instant. Note that I'm traversing the array in reverse, so that the row numbers remain correct. There is a chance this improves the performance, depending on the DOM code and the JIT strategies the browser uses.
[Edit: new jsfiddle with colour-coded cells to make it really obvious which rows have gone]
The problem is that for every row that you .remove(), the table is redrawn by the browser. To make it faster, remove the table from the DOM, take out the lines and put the table back at its place.
$table = $("#myTable").clone(true,true);//First true to keep events, second true to deepcopy childs too. Remove it if you do not need it to make it faster.
$table.find("tr").slice(250,300);remove();
$("#myTable").replaceWith($table);
You can use filter but I don't think it will be faster
$("#myTable tr").filter(function(index){
return index > 250 && index < 300;
).remove();
The problem is the browser tries to update the screen view of the DOM on each row removal.
You can do it by one of
removing the table, from the document, removing all rows and after
that inserting it back
cloning the table, removing elements on the clone, replacing the table with the clone
or if the amount of rows remaining is less than the ones remove, you could create a new table, insert all the rows in that and replace the existing table with the new one
The main idea is for the table to not be attached to the DOM when you do the removals, this way it will only update the view once all the rows are removed.
Is it possible you add an ID to each row? And then select the rows directly by ID and removing the rows? Like so:
var el = document.GetElementById("RowID_1");
document.removeChild(el);
jQuery is on top of Javascript. I guess using javascript directly is faster.
edit:
Ofcourse you can create a loop like this:
for(i=250;i<=300;i++)
{
var el = document.GetElementById("RowID_" + i);
document.removeChild(el);
}
edit 2:
Hide the table while editing so the browser does not update after each removal ? ;)
Try this . i hope it will help you
$("#myTable tr").slice(250, 300).html('');
I created a 3x3 table. Each column is generated using a function. The function basically returns a "td" element. Else where in the code I trigger an event based on some conditions. Whenever the event is triggered, I want to update one particular cell of the table. None of the cells have ids attached to them.
My question is how can I link up the "td" that I want to be updated with the event?
I have no specific context that refers to this td alone.
If you're not using any other tools like jQuery my approach might be to find the table which I assume you can do with Javascript. Then for each td element in the table inject a class to them that is unique. You could just give them numbers or something easy. Assuming the numbering never changes you now have an easy way to lookup the td elements later in your code without having to keep a reference to the td element you want.
Instead of adding a class you could just get all the td elements in the table and if you knew the 4th element was always the cell you wanted then you could just keep a reference to that td element.
Without using jQuery or anything, you can use DOM selectors such as .childNodes (and iterating till you're satisfied), .lastChild, .firstChild, .parentNode etc.
This link gets you through some examples.
Although, if you are using this a lot, create ID dynamically in JS. Like iterating once through all your table (with .childNodes), assigning an ID (like row1-col2) to every td. It will simplify the rest of your code.
Here is a jsFiddle to show you how with jQuery:
http://jsfiddle.net/HzBFE/
I currently have a website source code (no control over the source) which contains certain content that needs to be manipulated. This would be simple on the surface, however there is no unique ID attribute on the tag in question that can uniquely identify it, and therefore allow for further traversal.
Here is a snippet of the source code, surrounding the tag in question.
...
<td width="100%">
<!--This table snaps the content columns(one or two)-->
<table border="0" width="100%">
...
Essentially, the HTML comment stuck out as an easy way to gain access to that element. Using the JQuery comment add-on from this question, and some help from snowlord comment below, I have been able to identify the comment and retrieve the following output using the 'dump' extension.
$('td').comments().filter(":contains('This table snaps the content columns(one or two)')").dump();
returns;
jQuery Object {
0 = DOMElement [
nodeName: DIV
nodeValue: null
innerHTML: [
0 = String: This table snaps the content columns(one or two)
]
]
}
However I am not sure how to traverse to the sibling element in the DOM.
This should be simple, but I haven't had much selector experience with JQuery. Any suggestions are appreciated.
I am thinking you could use the siblings method:
$('td').comments().siblings('table').yourcode...
From the docs:
Given a jQuery object that represents a set of DOM elements, the .siblings() method allows us to search through the siblings of these elements in the DOM tree and construct a new jQuery object from the matching elements.
The method optionally accepts a
selector expression of the same type
that we can pass to the $() function.
If the selector is supplied, the
elements will be filtered by testing
whether they match it.
If you have any control over this code at all, put an id on the table.
If you have to do something nasty, perhaps you could use
var tables = $("table");
To get all tables and then ascertain the table in question by index...
$(tables[5]).css("color", "aqua");
This breaks as soon as a table is added or removed, but if you cannot add an id to the table it seems like a potential alternative.