Hi Guys
thank you in advance to those who will answer 
I have a 9V led common cathode and want to use ULN2803 will this circuit will work by adding a biasing resistor at the output ?
it tested it on normal transistor NPN transistor and it works well now and I'm exploring this ULN 2803 if it will do the same as it will make my project more neat and tidy.
thank you very much for the reply
Keep safe
Regards
I don't see what you want to achieve by adding that resistor. If your 9V led already has a current limiting device in it, no additional resistor is needed. The most tidy version of your circuit would leave them out, but perhaps I misunderstood what you meant with "tidy".
In fact, the additional resistor will only accomplish that there's always a small current flowing through the LEDs preventing them from being turned off entirely.
A ULN2803 is an 'open-collector' so like that your schematic won't work, the ULN2803's output will never go 'HIGH'. You should provide 9v to both the Anode and to 'COM' , and connect the Kathode to the ULN2803 'out' which will connect to GND if the input goes 'HIGH'. If you need a current limiting resistor for the led, you can put that between the Kathode and the ULN2803
For common cathode LED i prefer thing like UDN2981.
https://www.microchip.com/wwwproducts/en/MIC2981#additional-features
If your intention is that the 1k resistor supplies the current to the LED when the input to the ULN2803 is low, then when the input goes high the output of the ULN2803 shorts it out, making the LED go off then, yes, I suppose that would work.
It's ugly though! Horrible way to control LEDs! Do as @flashko suggested.
On a separate point, when someone asks a 'will it work?' question like this I always wonder why they are asking. This hobby makes it easy to experiment and try things for yourself, so try it and see what happens! At worst you are going to destroy some components costing not much, and even if you do you will have learnt something, which I think makes it worthwhile.
Hi,
What do you mean?
Is it a display or a single LED?
Can you please post a picture of it please?
Thanks.. Tom.. 
Hi Guys thanks you all for your comments and technical suggestion
here is the current circuit that I'm using with 6 individual x'stor NPN it is working.
I just want to lessen the components and just use the ULN2803 and will take up less space on my pcb.
Thank you anyway I already order the ULN 2803 and will test it.
Yes, your circuit will work with limitations as has been mentioned.
I think we would like to know what this "9V LED" actually is - whether it already includes the current limiting resistor and given that, what value? You may want a higher supply voltage for better brightness with your added series resistor.
If you are driving it from an Arduino, then the obsolete ULN2803 is a sad choice, a TPIC6B595 would allow you to drive it (or a number of them) with only three I/O pins.
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