Develop Reference

Grabbing text from a span tag

I have some code for Javascript using jQuery, and I've been wondering how to fix an element of it.
var dataGiven = +$("span.cost-in-usd:first-child").text();
However, the span tag is:
<span class="cost-in-usd" data-se="product-usd-value">42</span>
Is there a way of modifying my code in order for it to recognise data-se?

Yes, use data.
var datase = $('.cost-in-usd').data('se');
Some links;
http://api.jquery.com/jquery.data/
Here's a jsfiddle

The following will return the value of attribute
$('.cost-in-usd').attr('data-se');

How to remove/change an input value using javascript

How do I remove the value 'Anonymous' in this input that I have and replace it with a placeholder text 'Your name' using javascript/jquery? I don't have access to the HTML code.
This is what I have so far, but don't really know where to go from there.
document.getElementById('txtYourName').placeholder =' Your Name ';
HTML
<input id="txtYourName" type="text" value="Anonymous" name="txtYourName"></input>

Add this second line here...
A placeholder is only seen when the value happens to be blank. With the code below, you can set the placeholder, as well as erase the default value in your field.
document.getElementById('txtYourName').placeholder =' Your Name ';
document.getElementById('txtYourName').value = "";
Demo: http://jsfiddle.net/723vL/

You can use .val():
$('#txtYourName').val('');
or pure javascript using:
document.getElementById('txtYourName').value = ""
If you want to set new value then just put your value inside "", like:
$('#txtYourName').val('new value');
With jQuery, your final code should look like:
$('#txtYourName').attr('placeholder','Your name');
$('#txtYourName').val('');
Fiddle Demo
With pure JS, you final code should look like:
document.getElementById('txtYourName').placeholder ='Your name';
document.getElementById('txtYourName').value = "";
Fiddle Demo

That should do it, so long as you are running that script either on an onload event, jquery's ready event or at the very bottom of the page, once the DOM has been rendered.
Are you getting an error in your console?

try this
returns value:
$('#txtYourName').attr("value");
sets value
$('#txtYourName').attr("value", "");

use
document.getElementById('txtYourName').value ='some vaue';
if you are using jQuery then you can use
$("#txtYourName").val('some value');

Add code examples on your page with Javascript

I have a html code inside string
string_eng += '<b>Year Bonus</b> - bonus for each year</br></br>';
And I want to put this inside textarea, but when I do it, the result is:
- bonus for each year
It simply deletes all things inside the html tags. I just want to show all the code inside the string. I already tried <xmp>,<pre>, but none of them worked.
Thanks for any help.
EDIT.
Code with which I input data from the array to the textarea/code.
$('body').append('<code class="code_text"></code>');
for(var i=0; i<tag_list.length; i++){
var string='';
string+='---------------------------------------------------------------------------------\n';
string+='tag: '+tag_list[i][0]+'\n';
string+='nazwa_pl '+tag_list[i][1]+'\n';
string+='nazwa_eng '+tag_list[i][2]+'\n';
string+='tekst_pl '+tag_list[i][3]+'\n';
string+='tekst_eng '+tag_list[i][4]+'\n';
string+='\n\n\n';
$('.code_text').append(string);
}

I tried this using jsfiddle:
HTML
<textarea id="code"></textarea>
JavaScript
$(document).ready(function() {
var string_eng = '';
string_eng += '<b>Year Bonus</b> - bonus for each year</br></br>';
$("#code").html(string_eng);
});
Output (contained in textarea)
<b>Year Bonus</b> - bonus for each year</br></br>
Try it here: http://jsfiddle.net/UH53y/
It does not omit values held within tags, however if you were expecting the <b></b> tags to render as bold within the textarea, or the <br /> tags to render as line breaks, this wont happen either. textarea does not support formatting.
See this question for more information: HTML : How to retain formatting in textarea?

It's because you're using the jQuery .append method which seems to parse the string and insert it afterwards. I don't know jQuery at all, so there might be another special jQuery method, but here is a simple fix:
$('.code_text').append(document.createTextNode(string));
Edit:
I just read and tried the answer of Salman A. The "special jQuery method" exists and he used it. You can use this:
$('.code_text').text(string);

javascript: extracting text from html

I am getting html content as below:
var test='<div id="test">Raj</div>';
How can i retrieve value Raj from above html content using javascript.

It sounds like you're trying to extract the text "Raj" from that HTML snippet?
To get the browser's HTML parser to do your dirty work for you:
// create an empty div
var div = document.createElement("div");
// fill it with your HTML
div.innerHTML = test;
// find the element whose text you want
test = div.getElementById("test");
// extract the text (innerText for IE, textContent for everyone else)
test = test.innerText || test.textContent;
Or in jQuery:
test = $(test).text();

If you use jQuery (I cannot believe I just said that ;)) you can get at the content immediately you wrap it in $(test).html
Someone else will tell you how to get at the innerHTML using a selector since everybody here are jQuery gurus but me
Update: somebody just did while I was editing: javascript: extracting text from html - see comments or updates to that

var test = getElementById('test')
try that

Copying INPUT FILE value to INPUT TEXT with click in jQuery

I would like to copy the value of a input:file to input:text. I can do it with plan JavaScript but I will like to know how to do it with jQuery.
----JavaScript
// This what the script would look like with plain JavaScript
// It works fine. I just woulld like to know who to do it with jQuery.
function fakeScript() {
var filepath;
filepath = document.adminForm.tumb.value;
filepath = filepath.substring(filepath.lastIndexOf('\\')+1, filepath.length);
document.adminForm.tumbFake.value = filepath;
}

If you have something that works in "plain Javascript", it'll work with jQuery too : jQUery is just a library, that adds functions -- it doesn't prevent anything from working (or there is some kind of bug in it ^^ )

var fileValue=$("input[type='file']").val();
var inputValue=$("input[type='text']").val(fileValue);
cheers

You probably cannot use the value attribute of a file input with JQuery.
"The value attribute cannot be used with <input type="file">." - http://www.w3schools.com/tags/att_input_value.asp

To get the text value of a file from an <input type="file"/> element, use yourFileInputElement.files[0].getAsText("utf-8").