stevehopwoodforex.com • Getting to Know Empty4 Inside Out

Author:

ovo.cz [ Fri Mar 22, 2013 7:03 am ]

Post subject:

Re: Getting to Know Empty4 Inside Out

When working with DLLs functions, there are variables passed by reference, which are supposed to be modified by the DLL. With integers and doubles there is one and only solution - using arrays in place of a simple variables. But strings are tricky.
You may pass a string by its value (syntactically) and it works like if it were by reference (weird? yes).

Code: Select all

string outputString = "xxxx";
dllFunction(inputValue, outputString);

It works correctly, supposing, that the string had only been initialized by a constant (not variable) with a length not more than 254 chars. Why 254? The compiler wouldn't compile longer one.
So what if you need more than 254?
The first thought is adding more constants to a string like that:

Code: Select all

string outputString = "xxxx" + "xxxx";

But surprise --- this doesn't work. Passing this variable to a DLL no longer behaves like a reference (weird? yes).
So what? A workaround is often used, which converts strings into integers and vice versa. That works nice, but the code looks kinda complicated and unreadable.

Recently I noticed a simple trick that I did not know about. It is using Concatenate() to initialize the string. As many times as you need, to get the required length.

Code: Select all

string outputString = StringConcatenate("xxxx", "xxxx");

And the string behaves like a reference, again.

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Author:	Freedom787 [ Thu Mar 14, 2013 3:35 pm ]
Post subject:	Re: Getting to Know Empty4 Inside Out
Being unable to initialize Arrays with a variable frustrates me. Whether its proper coding or not, I like the idea of the code being more dynamic.

Author:	SteveHopwood [ Thu Mar 14, 2013 4:07 pm ]
Post subject:	Re: Getting to Know Empty4 Inside Out
Freedom787 wrote:Being unable to initialize Arrays with a variable frustrates me. Whether its proper coding or not, I like the idea of the code being more dynamic. You can use the ArrayResize() function to reinitialize the array to your variable size.

Author:	Freedom787 [ Fri Mar 15, 2013 3:43 pm ]
Post subject:	Re: Getting to Know Empty4 Inside Out
Wow, thanks Steve! Can't believe I never thought of that.

Author:	SteveHopwood [ Fri Mar 15, 2013 4:51 pm ]
Post subject:	Re: Getting to Know Empty4 Inside Out
Freedom787 wrote:Wow, thanks Steve! Can't believe I never thought of that. Hehe. The total tonnage of what I can't believe I never thought of over the years, would stop a charging bull elephant in its tracks.

Author:	cjthomson [ Wed Mar 20, 2013 3:51 pm ]
Post subject:	Re: Getting to Know Empty4 Inside Out
Does anyone know how to re-order the tab order for the keyboard shortcut (cntrl + tab). I have about 15 chart tabs on screen and when I hit ctrl + tab it seems to adopt a very random order i.e. it doesn't move from tab to tab in a left to right or right to left way, it jumps around. Any advice would be appreciated.

Author:	SatchFan [ Wed Mar 20, 2013 5:24 pm ]
Post subject:	Re: Getting to Know Empty4 Inside Out
cjthomson wrote:Does anyone know how to re-order the tab order for the keyboard shortcut (cntrl + tab). I have about 15 chart tabs on screen and when I hit ctrl + tab it seems to adopt a very random order i.e. it doesn't move from tab to tab in a left to right or right to left way, it jumps around. Any advice would be appreciated. If I remember correctly you need to do the following steps: 1. Click on the tabs in the order you want to view the charts. Make sure you click on all the tabs. (It may be easier to first click and drag all the tabs and put them in the order first by putting the first one you want to view to the far left and the next one to the right of that and so on.) 2. Once you have them in the order you want, then start clicking on each tab starting at the far left and work your way to the right. Take your time and make sure you click on all of them and the chart changes to the correct chart after you clicked on the tab. 3.Once you have clicked on all the tabs in the order you want then you should be able to use your keyboard to scroll through all your charts in that order. Enjoy! Let me know of that helps it has been a long time since I have done that. Peace, SatchFan

Author:	cjthomson [ Fri Mar 22, 2013 8:01 am ]
Post subject:	Re: Getting to Know Empty4 Inside Out
SatchFan wrote: Let me know of that helps it has been a long time since I have done that. Peace, SatchFan Thanks SatchFan - its worked as you said.

Author:	cjthomson [ Sun Mar 31, 2013 6:39 pm ]
Post subject:	Re: Getting to Know Empty4 Inside Out
Can anyone tell me what I should do with a .rar file. Which folder should it go into and what do I need to do to use it? Any help would be appreciated. Cheers.

Author:	SteveHopwood [ Sun Mar 31, 2013 9:21 pm ]
Post subject:	Re: Getting to Know Empty4 Inside Out
cjthomson wrote:Can anyone tell me what I should do with a .rar file. Which folder should it go into and what do I need to do to use it? Any help would be appreciated. Cheers. It is a file containing compacted files as in zip files, but using some blasted commercial compacting software that users are supposed to pay for. It infuriates me when people use them. Anyone here know of a free utility that extracts files from the damn things?

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