How to zero fill field from html input

[Don Martino]

I have an input field defined in html document. I want to make the field 8 characters, right justify the numbers entered and zero fill the leftmost bytes.

If user enters "1234" I want to use javascript to make field "00001234".

[Don Martino]

Any ideas? Do you understand the question?
User enters 3 numbers into html input field. I want to use javascript client side to create 8 byte field, right justifying the numbers and fill the remaining 5 bytes to left with 0's.

[Paul Clapham]

It should be quite easy to write a Javascript function which takes a string as a parameter and returns that same string, with zeroes appended at the left to make the length up to 8. Are you asking how to do that? Or how to get something to call that function? Don't know how to get it called at the right time? Or where to put the result?

So I guess, no, I don't really understand the question.

[Don Martino]

Thanks for response! I'm new to javascript and I'm trying to figure out how to do it, I mean creating string as parameter and appending 0's to left.

[Eric Pascarello]

The basics:

onchange

document.formName.elementName.value

length

for loop

Eric

[Nicolas Mejia]

Here is a easy function I made:

//STR_PAD_RIGHT = 1; STR_PAD_LEFT = 0;
function str_pad(input, pad_length, pad_string, pad_type){
for(i=input.length; i<pad_length; i++){
if(pad_type)
input = input + pad_string;
else
input = pad_string + input;
}
return input;
}

I hope it helps...

[Michael Angstadt]

Don Martino wrote: I'm new to javascript and I'm trying to figure out how to do it

W3schools.com is your friend. It provides tutorials and reference manuals for many web technologies, including Javascript.