How to calculate DS:[0040207A] manually?

How to get the result 77D507EA manually from DS:[0040207A] according to regi开发者_StackOverflowster info above? UPDATE

I see your using OllyDbg, so to make it a little relavent to your situation:

DS indicates that it(the address) is in the data segment, [0040207A] is the address in the data segment. if you goto (crtl + g in olly) address 0x40207A, you'll see some bytes, this is the pointer to MessageBoxA. just note that your missing the size of element pointed to by the address (in this case its DWORD PTR), the full instruction should be MOV EAX, DWORD PTR DS:[0040207A]

In the data dump(window in the bottom left), it should look something like: 0040207A EA 07 D5 77

In the CPU window, it might get properly analysed by olly(depends on the plugins and confings), in which case it'll look something like: 0040207A MessageBoxA EA 07 D5 77 User32.MessageBoxA

Also not, the address 0040207A might not be static, so going there will olly in a different session might not work, due to windows rebasing the virtualized binary

Update

It would appear that both your assembly knowledge and knowledge of x86 architecture is really poor, as such I would recommend that you read up on these subjects, wikipedia is a good start, else your not going to understand how addressing and pointers are handled on an assembly level