If select a color from Eyedropper tool and try to put it in stroke of any object, then it doesn't fills up in it's stroke instead it fills the whole object not the stroke. Eg say its a circle which is not filled but have only stroke on it. So, when I try to pick a colour from Eyedropper tool then it doesn't fill up on stroke of circle instead it fills the whole circle. So I have to note down the colour code value and write manually each value. Is there any time saving process in this???
Unfortunately, if you are sampling another vector object in Illustrator, the eyedropper tool isn't just copying the color value, it's copying the object's complete fill and stroke data. Your selected object will take on the sampled object's fill and stroke.
If it's a color you are using a lot in your project, you can try creating a new swatch and use that to apply to your strokes.
Create a new swatch:
Select the object you want to change the stroke color of. Click on the little "stroke" color picker in the top left corner of the Swatches palette:
Click on your new swatch to apply the color to the stroke:
You can make the stroke color active (X HOTKEY), then activate the picker (I HOTKEY), and shift click anywhere to grab color for your stroke.
The simplest way to only copy one color from an object to another without modifying all the properties is to drag the color from the color panel and drop it over the object we want to apply the color to.
Configuring the eye dropper every time, or working with swatches for such a simple task is slow and tedious.
One way to achieve what you are looking to do is clicking all of the strokes you want to change the color of and then clicking the Eye Dropper Tool, I as usual. Once the fill color has changed, click Shift + X to reverse the stroke and fill color. If you have no fill and a stroke color desired, this will work great. This is for instances, so may not work for every application.