JavaScript determines keyboard keys

Window.document.onkeydown =Disablerefresh;functionDisablerefresh (evt) {evt= (evt)?evt:window.eventif(evt.keycode) {if(Evt.keycode = = 116){     //Do something}}}keycode8 =BackSpace Backspacekeycode9 =Tab Tabkeycode12 =Clearkeycode13 =Enterkeycode16 =Shift_lkeycode17 =Control_lkeycode18 =Alt_lkeycode19 =Pausekeycode20 =Caps_lockkeycode27 =Escape Escapekeycode32 =Space Spacekeycode33 =Priorkeycode34 =Nextkeycode35 =Endkeycode36 =Homekeycode37 =Leftkeycode38 =Upkeycode39 =Rightkeycode40 =Downkeycode41 =Selectkeycode42 =Printkeycode43 =Executekeycode45 =Insertkeycode46 =Deletekeycode47 =Helpkeycode48 = 0equal Bracerightkeycode49 = 1Exclam Onesuperiorkeycode50 = 2Quotedbl Twosuperiorkeycode51 = 3Section Threesuperiorkeycode52 = 4Dollarkeycode53 = 5Percentkeycode54 = 6Ampersandkeycode55 = 7Slash Braceleftkeycode56 = 8Parenleft Bracketleftkeycode57 = 9parenright Bracketrightkeycode65 =a Akeycode66 =b bkeycode67 =C Ckeycode68 =D Dkeycode69 =e e eurosignkeycode70 =F Fkeycode71 =g Gkeycode72 =h Hkeycode73 =I ikeycode74 =J Jkeycode75 =k Kkeycode76 =L Lkeycode77 =m M Mukeycode78 =N Nkeycode79 =o okeycode80 =P Pkeycode81 =q q atkeycode82 =R Rkeycode83 =s Skeycode84 =T Tkeycode85 =u ukeycode= V

JavaScript determines keyboard keys