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Regex in javascript replace function

Am newbie to regex am trying to do some regex replace function in java script here is my content and code
jQuery("td[headers='name_head']").each(function (index, value) {
var text = jQuery(this).html();
if( text.indexOf('<a href=') >= 0){
jQuery(this).text(text.replace(/<a href=.*\"$/, ""));
}
});
Html content will be look like this
Calculate Points
i just want to remove only the value inside href ""
Please throw some light on this
Regards
Sathish

The text() method just retrieves the text contents which doesn't include any HTML tags. You can use html() method with a callback function where you can get the old HTML content as the second argument to the callback and based on the old value generate updated HTML.
The better way is to update the href attribute value of a tag to empty by directly selecting them, there is no need to loop over them since all values need to be empty.
jQuery("td[headers='name_head'] a").attr('href', '');
UPDATE 1 : In case you want to iterate and do some operation based on condition then do something like this.
jQuery("td[headers='name_head'] a").each(function(){
if(//your ondition){
$(this).attr('href', '');
}
});
or
jQuery("td[headers='name_head']").each(function(){
if(//your ondition){
$('a', this).attr('href', '');
}
});
UPDATE 2 : If you want to remove the entire attribute then use removeAttr('href') method which removes the entire attribute itself.
jQuery("td[headers='name_head'] a").removeAttr('href');

Why would you reinvent the wheel?
You don't need regex to achieve this, you can simply do it this way:
jQuery("td[headers='name_head'] a").attr('href', '');
It will set href to "" for all <a> elements inside td[headers='name_head'] so it will always respect your condition.

I haven't tested this code; but something like this should help, don't think you need to use regex for this;
$('a.DisableItemLink[href!=''][href]').each(function(){
var href = $(this).attr('href');
// do something with href
})
This piece of code selects all elements which have the class DisableItemLink with a location set and sets it to blank.
I am curious as to what you are trying to do in the larger scheme of things though, sounds like there might be better ways to go about it.
Reference: some good selector combinations for links

How to get input value with no id using JavaScript?

I have an editable DataTabe and when edit mode, the generated html is exactly as shown below:
<td><form><input autocomplete="off" name="value" ></form></td>
There is s TextBox as input and I need t get the value of this input. However, I cannot give id as there is no configuration of DataTable and I decided to get the value using Javaascipt. I have tried many different methods like closest() as shown below, but cannot get the value. Is it possible to grab it?
var $row = $(this).closest("tr");
$tds = $row.find("td");

You might use document.querySelector:
var input = document.querySelector('[name="value"]`);
Or, using jQuery, you could also use the same selector:
var input = $('[name="value"]');

var currentInput=null;
$("input").focus(function(e)
{
currentInput=e.target or this;//here you can get currently editing textfeild or may be $(this) if this is wrong
});
then you can get currentInput.value()

I see you are using jQuery; you can target the name attribute directly and to get a value of the input use .val(), like so:
$("input[name='value']").val();

Jquery get element by id, multidimensional array

I'm trying to get the value of a specific html input that is named like:
<input type="hidden" value="." id="grid[0][0]">
where [0][0] could be any value within a foreach loop.
using Jquery:
var currVal = $('#grid['+x+']['+y+']').html();
I'm getting an undefined value. Not sure whether it's a syntax problem. I haven't found a similar example so I'd appreciate any help on this. Thanks!

It actually is a syntax problem. jQuery interprets "#grid[...]" as an HTML element with the ID "grid" and some attribute (or other meta stuff) just like CSS would.
To solve simply escape the [ and ], like this:
$('#grid\\[' + x + '\\]\\[' + y + '\\]').val()
That should do it :)
Edit: As noted by Josh Crozier, the html() method is supposed to be used in normal tags (like div). For input, select or textarea you should use val() -- Docs on that: http://api.jquery.com/val/

You can also do :
var currVal = $('input[id="grid['+x+']['+y+']"]').val();

jquery escape square brackets to select element

Consider a input element
<input id="meta[152][value]" type="text" />
Here the input field is dynamically generated. I need to select that field. So I used,
alert($('#meta[152][value]').val());
But this seems to be invalid. After searching I found, that the "square brackets" need to be escaped like #meta\\[152\\]\\[value\\]
So how to do that ?
I currently use this code,
var id = "#meta[152][value]" // (I get this value by another method) I need the escaping to be done here. So that i can use as
/** I need the value of id to be escaped using regex,replace or any other method
to get #meta\[152\]\[value\]
and not manually **/
alert($(id).val());
Your suggestions will be helpful !

The following should work:
alert($('#meta\[152\]\[value\]').val());
or
var id = "#meta\[152\]\[value\]";
alert($(id).val());
Working Example
Conversion Function:
function ConvertValue(id)
{
var test = id.replace(/[[]/g,'\\\\[');
return "#" + test.replace(/]/g,'\\\\]');
}
Conversion Example

If you feel more comfortable without escaping you also use the attributes selector and search for the element with that id like this: $("[id='meta[152][value]']")

The simplest way is just to use the regular getElementById, which requires no escaping:
document.getElementById("meta[152][value]").value;

this shoudl work for you, you almost had it:
$(document).ready(function() {
var id = "#meta\\[152\\]\\[value\\]";
alert($(id).val());
});

Um, just put the escaped value right in your string.
var id = "#meta\\[152\\]\\[value\\]";
See it working here

You can use the _.escapeRegExp method from the Lodash library.
console.log($('#' + _.escapeRegExp('meta[152][value]')).val());
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js"></script>
<input id="meta[152][value]" type="text" value='Test' />

jQuery: Using Selectors on HTML from an Attribute

I have some HTML that is stored as an attribute on a tag. I can access it in jQuery using
$("input[id$='_myField_hiddenSpanData']").attr("value")
This looks like this:
"<span id='spantest\user' tabindex='-1' contentEditable='false' class='ms-entity-resolved' title='test\user'><div style='display:none;' id='divEntityData' key='test\user' displaytext='Test User' isresolved='True' description='test\user'><div data=''></div></div><span id='content' tabindex='-1' contenteditable onMouseDown='onMouseDownRw();' onContextMenu='onContextMenuSpnRw();' >Test User</span></span>"
I would need the value of the key attribute (test\user). Can I somehow tell jQuery to parse a block of HTML and apply selectors to it? I found I can wrap it into a new jQuery object by wrapping it into another $(): $($("input[id$='_myField_hiddenSpanData']").attr("value")) but I still did not manage to apply a selector on it.
Any hints? And no, sadly I do not control the markup that generates the hidden field.

Wrap your crappy markup with a jQuery object, and then use the find function to apply a selector to it...
var crappyHtml = $("input[id$='_myField_hiddenSpanData']").attr("value");
var key = $(crappyHtml).find("div[key]").attr("key");
alert(key);

Try this:
var html = $("input[id$='_myField_hiddenSpanData']").attr("value");
var user = $(html).find("#divEntityData").attr("key");
alert("user=" + user);

You should be able to pass it as a context. Does this work?:
$('#divEntityData', $($("input[id$='_myField_hiddenSpanData']").attr("value"))).attr('key');