my phone not working

[sumaiya]

i ve iphone 4 ,but my phone 's display is not working . its black. i had a phone call. ..then i received after that ...the phone is black ! i tried to call from another handset to my number ....it is ringing ...but screen is black!

 

[bab2010]

Perform a hard reset and your screen will be back. To do the hard reset, press and keep both home and power on/off buttons until the screen light up with the Apple logo, then you let go both buttons.

 

[EWyatt]

sumaiya, did the previous suggestion help?