Writting code to take ScreenShots (C++)

[st4rv1n9]

Hey everyone...i'm trying to write a C++ program that will pretty much run in the background and will take a screenshot whenever the user presses a certain key. But the big thing that i want the program to do is read in a number from a file (this number is to be used to keep track of naming the screen shots), take the screen shot when they press the defined key, and then automatically save it into the directory the program is running from. i've got all the code written accept for the actual code that takes the screen shot. i can't seem to figure it out. anyone care to help?

main()

{

read in number from file

while(true)

{

if getasynckeystate(key)

{

screenshot();

increment number

}

if getasynckeystate(vk_escape)

break;

}

output new number

exit

}

basically i need to know what i should do in screenshot().

i've actually made a class called ScreenShot, so that if i come up with any other cool ideas i can just throw them in a function inside of it. well, any help would be much appreciated. thanks!