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how to call a function using dynamic function name (parameterized) in nodeJS

I am able to call function in my code.. however I want to make my calling function name as variable so that it can call any function based on my variable value ..
reportPage.accounts()['catType']()
so here I want to make catType as variable, so that I can pass any value.. How to declare/call here..

You replace the string literal with the variable, exactly as you would anywhere else.
var thing = 'catType';
reportPage.accounts()[thing]()

How to set javascript variable to flask template variable using javascript

I want to set the javascript variable value to flask template variable in javascript. What I am trying is
$(document).on("click", ".prepopulate", function () {
var myBookId = $(this).data('id');
alert(myBookId); // The value is showing proper
{% set tempVar = 'myBookId' %}
alert ({{tempVar}})
});
But it's giving an error instead (UndefinedError: 'list object' has no attribute 'myBookId'). What is the way to set the template variable in javascript using javascript variable?

You want to use set like this:
%SET{"tempVar" value="myBookId"}%

You cannot do this because jinja runs before the page loads and on the server side but the javascript code is executed when the page is loading and on the client side (browser) so your myBookId variable doesn't exist for jinja (see this answer for more info). A way to achieve what you want is to use ajax. See here an example.

If you look at your rendered HTML you will see
alert (myBookId)
Unless you define a variable called myBookId, this is not valid JavaScript. You need to wrap the string value in quotes.
alert('{{ myBookId }}')
An even better way to do this is to let Jinja decide for you if quotes are needed.
alert({{ myBookId|tojson|safe }})
This will wrap string values in strings, leave integers alone, and use JavaScript booleans.

cannot pass string to function

I'm using javascript and I try to pass a string to a function , like so
//example string
var f="a";
//add button that sends the value of f to the function
document.getElementById("mydiv").innerHTML="<input type='button' id='myButton' value='Click here' onclick='gothere("+f+");'> ";
function gothere(a){
alert(a);
}
I never see the alert and in console I see a is not defined (refers to the f I guess?)
If i set the f var to be a number then I see the alert.
What am I missing?
Thanks in advance
EDIT
I was thinking maybe something like
var buttonnode= document.createElement('input');
document.getElementById("mydiv").appendChild(buttonnode);
buttonnode.onclick=gothere(f);
Wont work for the same reason?

When your HTML get's rendered, you get onclick='gothere(a);', but the actual a variable doesn't exist in this context, you want to pass the value of f, as a string, so you'll need to use onclick='gothere(\""+f+"\");'. Note the extra quotes inside the parens. This will render to onclick='gothere("a");' thus passing the string.
When using a number, it works, because calling onclick='gothere(5);' is valid, since a variable can't be named 5, and it passes the number.

Actually, you don't have an a in your code. You are using variable f to denote a. So using this would help you:
var f="a";
// write the remains of the code as they are..
function gothere(f) {
alert(f);
}
Now when you'll call the function, there will be an alert of a in the browser.
Also, try wrapping the content in "" double qoutes to let the code understand that this is a string not a character.
For onclick use
onclick='gothere(" + f + ")'
And now, its onto you to write the value. Maybe the issue is because you're not writing the value for the f.
Try inpecting the error. I am sure there won't be anything.
Or try using the attribute field and change it using jQuery.

How about fixing your code ? You are missing the quotes around the value denoted by variable F.
Hence, when variable F is parsed, the function becomes gothere(a) . while a is not a defined variable (but its a value) and hence the error.
Try this !
document.getElementById("mydiv").innerHTML="<input type='button' id='myButton' value='Click here' onclick='gothere(\""+f+"\");'> ";
The modified part is onclick='gothere(\""+f+"\");'> "
This should work for you !

function parameter string value image dynamically from JSON. Since item.product_image2 is a URL string, you need to put it in quotes when you call changeImage inside parameter.
My Function Onclick inside pass parameter.
items+='<img src='+item.product_image1+' id="saleDetailDivGetImg">';
items+="<img src="+item.product_image2+" onclick='changeImage(\""+item.product_image2+"\");'>";
My Function
<script type="text/javascript">
function changeImage(img)
{
document.getElementById("saleDetailDivGetImg").src=img;
alert(img);
}
</script>

You need to use single quotation marks for value arguments (see #Nis or #CDspace answer).
Better way to handling dynamic clicks or other events is event binding. See jQuery event binding for example.

Assignement of a variable inside a concatenation

I have a global variable var num_tab=1;, a function that creates a link a href :
function Addsomething()
{
$("#tout").html("<a style=\""+"margin-left:-20px;"+"\" onClick=\"eval(num_tab=2)\" href=\""+"#tab1"+"\" data-toggle=\""+"tab"+"\">SELECT</a>");
Bla,Bla..
$("#champ1").append('<li id=\"1\" class="champ" onclick="insertAtCaret("sousTab'+num_tab+'");" value=\"1\">1</li>');
}
What i want to do is to create a href that when clicked changes the value of the variable num_tab, but if you can see the href is inside a jquery html(), which makes me confused about how to assign a value to the variable. I almost tried everything: onClick=\"num_tab=2\",onClick=\""+num_tab+"=2\"
Actually i tried something: when i write onclick='num_tab=2;alert("+num_tab+");' i still get the initial value of num_tab, seems it's more like a problem of local and global variable and i can't figure out it yet.

Please don't use eval(). It's insecure and not the appropriate tool for this job. Just assign a function to the onclick:
$("#tout").html("<a onclick='set_num_tab(2)'">); //fill out the rest of this line
function set_num_tab(value) {
num_tab = value;
}
That should give you an idea of how to do it. btw there's no reason you can't use single quotes around an onclick like that.
Alternately, this would work:
$("#tout").html("<a onclick='num_tab=2'">);
But that's pretty messy. I try to avoid inline JavaScript.

how to call javascript function from client side on anchor click

I have javascript function sample('textValue') and have to call at server side on anchor click. I tried below code
string text="xyz";
anchor.Attributes.Add("onclick","javascript:sample('"+text+"');
but the value of the text is not assigning correctly. Encoded string gets added. The result in view source looks like
javascript:sample('xyz')
But i need javascript:sample('xyz')

What server/backend language do you use? PHP? Do you use any framework (Zend, CakePHP...)?
On the JS side do something like this:
Option 1
Test
Option 2
Test
<script type="text/javascript">
document.getElementById('clicky-clack-link').onClick = function() {
sample('test');
};
</script>
Note: Also check out jQuery if you haven't.

I wonder if you could just do this:
string text="xyz";
anchor.Attributes.Add("onclick", function(){ sample(text); } );
What does it do? Well, the onclick handler takes a function with no arguments, right? That is, what to do if somebody clicks the link. If you're coding this by hand in HTML, you can use the javascript:a_statement_goes_here to describe the code to run. I expect the browser will just create a function out of that. Since you're assigning this in JavaScript, you have to do that yourself (unless you write out to the document - that might work) and assign the function. But you don't have such a function yet - you have one sample that takes an argument - hence the anonymous function closing the text argument.
This is based on the assumption, that the above is actually client-side code. I'd be very surprised, if JS didn't allow you to assign a function to an attribute. In fact, I think the problem you are running into, is JavaScript trying to be very smart and make sure assigning a string, will stay a string - that is why your ' got encoded.
Have a go, tell me how it went. Ta!