|
Thanks that’s it I wanted to calculate the number of characters the control can hold on a line
|
|
|
|
|
ForNow wrote: I wanted to calculate the number of characters the control can hold on a line
It depends on the font your control is currently using.
|
|
|
|
|
|
If your current font is a "proportional" one (like Arial, Times New, ...) then it is not possible to calculate the number of characters in a line in a common case.
It will always depend of the text itself. Example:
the text "WWW" needs much more pixels than "111".
But for non-proportional fonts (like Courier New) both need the same number of pixels.
|
|
|
|
|
I understand that this is the font statement from resource file dialog definition "FONT 8, "MS Shell Dlg", 400, 0, 0x1" I basically editing for hex characters so my GetTTextExtent string is "0123456789ABCDEF" these characters seem like the size even without a Font like courier new
|
|
|
|
|
That's a proportional font, a 1 will take far less space than an E. If spacing is important then you should use a fixed font in your edit control.
|
|
|
|
|
Have you considered deriving your own class from CEdit, something like:
class MyCustomEdit : public CEdit
{
}Then as each character is typed into the control but before the control is updated, figure out what line the cursor is on (I haven't used MFC in a few years so I'm not sure what these two messages would be). If there is room, let the character through, otherwise not.
"One man's wage rise is another man's price increase." - Harold Wilson
"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons
"You can easily judge the character of a man by how he treats those who can do nothing for him." - James D. Miles
|
|
|
|
|
probably WM_CHAR and wparam is the keystroke truth that would also save me time on the editing as I can see if it is a valid hex character was entered rather then do GetWindowText to read the entire control
Thanks
|
|
|
|
|
This class may provide all the functionality of a DDV macro
|
|
|
|
|
HI,
I'm updating my C++ application in to multi thread application in VisualStudio 2013.
In main(), thread's was created by CreateThread()and inside the thread's classA ObjA(); was created & called the function.
In the classA it call another dll method.
Dll was include in to the project through properties->Linker.
Problem was when objA called dll method , application throws access violation reading location.
But without multi-thread it works normal.
Accessing dll method from multi-thread is same way as normal or any other things needed for accessing.
Thanks in Advance.
|
|
|
|
|
You need to use the debugger to check exactly what caused the access violation. Are you sure the DLL is totally thread-safe?
|
|
|
|
|
What is a type of your project?
What is a type of a DLL?
|
|
|
|
|
I perform some experiments with the cpp code and I got -nan values. Can anybody tell why I might get these values
modified 29-Jan-21 21:01pm.
|
|
|
|
|
Because the math operations performed by your code result in a NaN?
You cast an integer with at least the relevant most signficant bits set to float or double?
You have a buffer overflow writing such a value to the memory of a float or double?
Without seeing code, we can't tell you for sure.
|
|
|
|
|
2 most likely reasons:
Invalid math e.g. division by zero, or use of uninitialized variables. Without seeing your code, and input, we can't know.
|
|
|
|
|
ahem... Division by zero in general produces a (signed) Inf, not a NaN.
Software rusts. Simon Stephenson, ca 1994. So does this signature. me, 2012
|
|
|
|
|
Because what ever you are doing, the result is not a number.
"One man's wage rise is another man's price increase." - Harold Wilson
"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons
"You can easily judge the character of a man by how he treats those who can do nothing for him." - James D. Miles
|
|
|
|
|
|
Hi
I have some questions regarding storage allocations. I know there is default heap value every exe or DLL gets. You can make that bigger or smaller /HEAP
I am guessing this is where the "new" operator gets storage.
using GetProcessHeap gets storage from this heap
If I don't want to bump heads with that I do a HeapAlloc initially the three paramters all zeros
But I "THINK" even if I do a HeapAlloc for 20 byes it really gets 1K
if I see that during my processing I need more I do a HeapRealloc using the same pointer for return value and 1st parameter I get more storage
I don't know if this better than using new
would anyone have any input ?
|
|
|
|
|
|
ForNow wrote: But I "THINK" even if I do a HeapAlloc for 20 byes it really gets 1K
I don't know if this better than using new
There is a very specific reason for using HeapAlloc and nothing you posted suggests you need that.
And not a good idea to attempt to circumvent C++ compiler allocations unless you have identified a specific need and you understand exactly how allocations work.
If you have some limited need or just want to mess around then you can override allocations for a specific class (one class only) and control it in fine detail. And do so knowing that you are not as likely to mess up the rest of the application doing it.
Alternatively find several open source allocators and heaps and examine how they are implemented first to understand what happens with heaps.
Keep in mind that if you do attempt to control your own allocations you can completely destroy the application (runtime) because you can end up overwriting memory that has nothing to do with what you think it should. So do it very carefully.
|
|
|
|
|
The run time has it own heap I think the default heap
When I create my heap I’m segragting the allocations
|
|
|
|
|
ForNow wrote: The run time has it own heap I think the default heap
Modern OSes generally have at least two allocators. So in C++ the OS provides space to the app and then C++ itself manages that heap with its own allocator. Same is true for Java and C#.
ForNow wrote: When I create my heap I’m segragting the allocations
Not sure that what that means.
An heap already represents a segregation. The C++ heap (every one I have looked at going back decades) dynamically manages blocks that it requested from the OS. Then on top of that it lays down a simple (or even complex) traditional heap. Then when you use 'new' (presuming you do not otherwise provide an allocator) it uses that existing API to request an amount of space appropriate for usage. Generally the allocation is exact to the structure.
The structure might have padding but that is intrinsic to the structure and not the allocation.
|
|
|
|
|
New works well when you now Exactly howvmuch storage you want I.e a object or class
In my case I am capturing user input and not quite sure thus HeapReAlloc
|
|
|
|
|
ForNow wrote: New works well when you now Exactly howvmuch storage you want I.e a object or class
That is not true.
For an object in C++ you must ALWAYS allocate at least as much space is needed for the object. You can allocate more but it will be wasted.
One can force C++ to use space that is less but that would be nothing but bad programming.
ForNow wrote: In my case I am capturing user input and not quite sure thus HeapReAlloc
All that means is that you are dynamically allocating the space. Which is something that C++ allows directly. You do not need to use a system API method to do that.
As I previously pointed out HeapReAlloc has a specific purpose. And what you just described here is an inappropriate use of that. And one that could lead to resource (memory) starvation if you are not careful how you use it.
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
