IsKeyPressed

Syntax:

IsKeyPressed key

Returns true if key is currently pressed down. Key values are stored in Windows header files.

Sample Key IDs

1   Left Mouse Button
2   Right Mouse Button
4   Middle Mouse Button
---
20  Caps Lock
---
32  spacebar
---
48  0
49  1
50  2
...
55  7
56  8
57  9
---
65  A
66  B
67  C
...
88  X
89  Y
90  Z
---
96  NUM0
97  NUM1
98  NUM2
...
103 NUM7
104 NUM8
105 NUM9
106 NUM*
107 NUM+
109 NUM-
111 NUM/
---
112 F1
113 F2
114 F3
...
123 F12
...
127 F16 
---
160 left shift
161 right shift
162 left control
163 right control

A longer list can be found here

Notes

This function doesn't return a value while a messagebox is being displayed, presumably because input is switched over to the messagebox.