What type is lparam

Since nobody knows how to pronounce his last name, they picked the country he was born in and called it Hungarian notation. The Windows group adopted it as well, but picked the "bad" kind, System Hungarian. Where the first letter s of the identifier is chosen to note the type of the variable.

As opposed to the "good" kind, Apps Hungarian, which selects the prefix by the logical type name instead of the physical type name. Simonyi's version. So it is L as in Long, W as in Word. A clear problem with System Hungarian is that it doesn't work so well anymore when the architecture changes. So ignore these prefixes, they're just an historical accident. Very hard to diagnose problems occur when you don't, a common question here. Please have a look here in MSDN to have a complete list.

You can see basically the types eventually pointing to the same size bits: the only real difference is if you are using windows 32 or In term of usage meaning, they are general pourpose parameters you can use depending on what the window procedure needs to do.

The actual meaning of the wParam and lParam parameters' content depends on the particular message being sent; they are just generic buckets for message parameters.

So it's quite likely that you won't be able to circumvent unsafe type casts. So I need to use them as IntPtr. Am I safe with int or better IntPtr?

Asked By: Bitterblue. Improve this question. Mark Heath Mark Heath If the MSDN documentation was properly hyperlinked it would have saved me a lot of bother.

Might be a lazy question On the other hand it's the top answer at google when searching for wparam, so your not the only one that want a fast answer, and now everyone gets just that! StackOverflow is not about "laziness" it about documenting things people may not understand. There is way more useful information below than trawling the headers could ever provide. Anyone who downvoted this question should leave this site and instead spend their time adding elitest RTFM answers on lame-programming forums.

JesonPark: This question is tagged c. Show 4 more comments. Active Oldest Votes. Improve this answer. The red, green, blue RGB color value 32 bits. A variable whose value is to remain constant during execution. A bit unsigned integer. This type is declared in IntSafe. An unsigned long type for pointer precision. Use when casting a pointer to a long type to perform pointer arithmetic. Also commonly used for general bit parameters that have been extended to 64 bits in bit Windows.

This type is declared in BaseTsd. A floating-point variable. A handle to an accelerator table. Half the size of a pointer. A handle to an object. A handle to a dynamic data exchange DDE conversation. This type is declared in Ddeml. A handle to a DDE conversation list. A handle to DDE data. A handle to an internal drop structure. This type is declared in ShellApi. A handle to a deferred window position structure. This type is declared in WinUser. A handle to a GDI object. A handle to a global memory block.

A handle to an instance. This is the base address of the module in memory. A handle to a registry key. An input locale identifier. A handle to a local memory block. A handle to a module. The is the base address of the module in memory. A handle to a display monitor. A handle to a palette. A handle to a pen. A handle to a resource. A handle to a DDE string. A bit signed integer.