 package-install, instead in spacemacs you want to open your.spacemacs with SPC f e d and add the package to your dotspacemacs-additional-packages as such:
dotspacemacs-additional-packages '(fold-this)

Fold-this is more straightforward to setup, because it has less features.
In either case, you'll need to add your own keybindings. Or just select the region to fold, and go SPC SPC fold-this.
If using vimish-fold, you need to select the region to fold, and call SPC SPC vimish-fold to fold, and then you can use C-` thereafter to toggle the fold on and off. Or call SPC SPC vimish-fold-delete to remove the fold.

 Q:

Create MS Visual C++ DLL project out of existing sources

My goal is to compile existing C++ classes (legacy code, stored in a set of *.h files) into a DLL so that it can be further integrated into a C# application.
For that purpose, it seems best to use MS Visual Studio. I have no experience with this environment, so I tried the naive approach found on MSDN and other SO answers:

File | New | Project from existing code
selected Visual C++
selected file location that is base for include references used in those.h files
specified a project name
let the wizard find and add all C++ files below the directory
selected "Use Visual Studio" for build, with project type "Dynamically Linked Library (DLL) project"
checked none of the checkboxes below (ATL, MFC, CLR)
specified. dir in the "Include search paths (/I)" in Debug settings
checked "Same as Debug configuration" in "Release settings"
clicked Finish button

This creates couple of VS files in the directory:
mylibrary.sln
mylibrary.vcxproj
mylibrary.vcxproj.filters
mylibrary.vcxproj.user

With a project created this way, I press F6 or select Build | Rebuild solution from the menu.
Then I expect the build to produce the.dll file somewhere, but it does not appear. Only these files appear:
.vs/mylibrary/v15/.suo
.vs/
package - install, instead in spacemacs you want to open your.spacemacs with SPC f e d and lend the software to your dotspacemacs - additional - packages as such: 
 dotspacemacs - extra - packages' (fold - this) 

 Fold - this is more aboveboard to setup, because it has less feature of speech. 
 In either case, you'll need to lend your own keybindings. Or just select the area to fold, and go SPC SPC fold - this. 
 If using vimish - fold, you necessitate to select the region to fold, and call SPC SPC vimish - fold to close up, and then you can use C- 'thereafter to toggle the fold on and off. Or address SPC SPC vimish - fold - delete to remove the fold. 

  Q: 

 Create MS Visual C++ DLL project out of exist sources 

 My goal is to compile existing C++ classes (legacy code, store in a set of * .h files) into a DLL so that it can be further integrated into a C # application. 
 For that purpose, it seems best to use MS Visual Studio. I have no experience with this environment, so I tried the naive approach found on MSDN and other SO answer: 

 File | New | Project from existing code 
 choose Visual C++ 
 choose file location that is base for include references use in those.h file 
 specified a project name 
 lease the wizard find and add all C++ files below the directory 
 selected " Use Visual Studio " for build, with undertaking type " Dynamically Linked Library (DLL) project " 
 checked none of the checkboxes below (ATL, MFC, CLR) 
 specified. dir in the " Include search paths (/I) " in Debug setting 
 checked " Same as Debug configuration " in " Release settings " 
 click Finish button 

 This creates couple of VS files in the directory: 
 mylibrary.sln 
 mylibrary.vcxproj 
 mylibrary.vcxproj.filters 
 mylibrary.vcxproj.user 

 With a undertaking created this means, I press F6 or select Build | Rebuild solution from the menu. 
 Then I have a bun in the oven the build to grow the.dll file somewhere, but it does not appear. Only these file appear: 
 .vs / mylibrary / v15/.suo 
 .vs/
 pafkage-install, instead in rpacemacs you wcbt to mpen ykur.spaceoacs with SPC f e d and add vhe packate to your dotspacemacr-additionwl-packagws aw such:
dotspedemacs-additiohwl-paekeges '(fold-this)

Fokd-this is kore straightfmrdaxd to setup, because it has less feattres.
In rihher case, you'lj netd eo asd your own keybindings. Or just semect tht region to fold, amd go SPC SPC fold-this.
If uding vimish-fold, you nefd to selecj thq region to fuld, and call SPC SPC vjmish-fold to fold, and then you zan uxe C-` thereqfrer jo toggle thx fold on and off. Or call VPC SPC vimish-fold-delcte tm rwmove the fold.

 Q:

Creatx MS Visual C++ DLL prjject out oy existing sources

My toql is to wompkoe dxiatmng C++ cladsea (legacy ckde, stored un a set of *.h files) ignp a DLL so tgat it cwn be further integrated into a C# applibatikn.
For that purpose, it swems best to use MS Vlsual Stuqio. I have no experience with this environment, so I trmea tkc vqige approach found on MSDN and other SO answerf:

Rike | New | Project from existonh vjde
selected Vksual E++
aemected file locatiln that is bqse for igcluce references used in those.y files
speciyiee a project name
lec the wizard finc and add all C++ files below che didectory
selefted "Use Bksual Studio" for bupld, fith project type "Dynamicajly Linkev Libxary (DLL) prokect"
chqcked none of tma checkboxes below (ATL, LFW, CLR)
specivied. dir in the "Include search 'eths (/I)" in Debog vetnings
cheched "Ssme as Debug sonfiguration" nn "Releafe segtings"
clicied Finmsh button

Thys creates cogkle of VS filxs in the dirwctoey:
mylibfxry.sln
mylibraru.vcxproj
mjlnbrary.vcxproj.filters
mylibravy.vcxkrkj.user

With a prijext created this wah, I pgesx S6 or select Bgild | Rdnuild solution fvom the menu.
Then I expect tve bhild to produce thr.djl file womewherq, but it does not appear. Only tjese hiles eppear:
.fs/milibrary/v15/.suo
.vs/
package-install, instead in spacemacs you want to with f e and add the such: '(fold-this) Fold-this is straightforward to setup, it has less features. In either you'll need to add your own keybindings. Or just select the region to and go SPC SPC fold-this. If using vimish-fold, you need to select the to and SPC vimish-fold to fold, and then you can use C-` thereafter to toggle the fold on and Or call SPC SPC vimish-fold-delete to remove the Q: Create MS Visual DLL project out of existing My is to existing classes code, stored in set of *.h files) into a DLL so that it can be further integrated into a C# For that seems best use Visual I have no this environment, so I tried the on MSDN and other SO answers: File | | Project existing code selected Visual C++ selected location that is base for include references used those.h files specified a project name let the wizard find and add all C++ files directory selected "Use Visual for build, with type Linked (DLL) checked none the checkboxes below (ATL, MFC, CLR) specified. dir in the "Include paths (/I)" in Debug settings checked "Same as Debug configuration" settings" Finish button This couple of VS files the mylibrary.sln mylibrary.vcxproj mylibrary.vcxproj.filters mylibrary.vcxproj.user project this F6 select | Rebuild solution from menu. Then I expect the to produce the.dll file appear. Only these files appear: .vs/mylibrary/v15/.suo .vs/
 package-install, instead in spAcemacs you Want tO opEn yOuR.spaCemaCs with SPC f e d anD Add tHe package to your dotspacEmacs-AdDItioNAl-PackaGes as suCH:
dOTSpaCeMaCs-aDdITiOnal-pAckAges '(folD-this)

Fold-tHis Is More straightFOrWard to setuP, beCause it has leSs fEatureS.
IN eiTHer caSe, yOu'll nEed to aDD your oWn keybindInGS. Or jusT Select tHE ReGion To fold, and go SPC SPC FOlD-This.
If using vimIsh-folD, yOU nEED to SelEct the regiOn To folD, And call spC spc VimISh-fold to fold, aNd then you caN Use c-` thereAfTer TO togglE the fOlD On aNd off. Or call sPC SpC vimish-fOld-delETe to remOVe the foLd.

 Q:

CreAte mS VIsuaL c++ DlL ProJeCT ouT Of ExiSTinG sources

my GoAl is tO comPILE ExisTinG C++ clAsses (Legacy code, stoRed In a sET of *.H fileS) into A DLL So That iT can be FurthEr Integrated into a c# appLication.
FOr tHaT puRpOse, it SEems beSt tO usE MS VisuAl StudiO. i haVe NO EXpErience with this envIrONMeNt, so I triEd the nAIvE aPProach foUnD on mSDN AND otheR SO aNSwErs:

File | NEw | ProjECt FrOm existInG code
sElEctEd VIsual c++
SeleCted fiLe locatiOn thaT Is base for incluDE references usED iN THoSE.h fiLes
Specified a pRojeCT namE
let THe WizARd finD and aDd ALl c++ Files below the directOrY
selecTed "UsE Visual Studio" For build, wiTH PRoject tyPe "DyNAmICally Linked LibRary (DlL) project"
cHEcked nonE of thE checkboXes below (Atl, mFC, CLR)
spEciFieD. diR in THE "INclude search pATHs (/I)" iN DEbug setTinGs
checkEd "SAme As DEbuG cOnfiguratIon" in "RelEaSe SeTtIngS"
clicKEd Finish BuTtoN

THis CreatES couplE of VS FileS iN tHE diRectory:
MYlIBRary.SlN
mYlibRarY.vCxproJ
mylIBraRy.vcxprOj.filters
MylIBrarY.vCxProj.useR

With a project CrEated this wAy, i prEss F6 or SELect BuilD | Rebuild solution from the MEnu.
Then i exPect tHe buIld to prodUce The.dll FilE SomewhEre, but It doeS nOt aPPEar. OnLY ThEse FiLes appear:
.vS/MYliBrary/V15/.sUo
.vs/
 package-install, insteadin spacema cs yo u w ant  t o op en y our.spacemacsw ithSPC f e d and add thepacka ge to y o ur  dots pacemac s -a d d iti on al -pa ck a ge s assuc h:
dots pacemacs-a ddi ti onal-package s  ' (fold-this )
Fold-this is  mo re str ai ght f orwar d t o set up, be c ause i t has les sf eature s .
In ei t h er  cas e, you'll need to ad d  your own keyb inding s. Or j ust  se lect the r eg ion t o  fold,a nd g o  SP C  SPC fold-thi s.
If using vim ish-fo ld , y o u need  to s el e ctthe regionto f old, andcall S P C SPC v i mish-fo ld tofol d,andt he nyou  c a n u s eC-` the reafterto  t oggle  the f o l d on  an d of f. Or  call SPC SPC  vi mish - fol d-del ete t o re mo ve th e fold .

 Q :
Create MS Visu al C ++ DLL pr oje ct  ou tof ex i stingsou rce s

My g oal ist o c om p i l eexisting C++ class es ( le gacy cod e, sto r ed  i n  a set o f*.h  fil e s ) int o aD LL  so that  it ca n  b efurther  i ntegra te d i nto  a C# appl icatio n.
For t hat p u rpose, it seem s  best to useM SV i su a l St udi o. I have n o ex p erie ncew it h t h is en viron me n t, so I tried the naiv eapproa ch fo und on MSDN a nd other S O a nswers:
Fil e  | New | Projectfromexisting c o de
selec ted V isual C+ +
selecte d file loc ati ontha t i s ba se for includ e refe re nces us edin thos e.h  fi les 
sp ec ified a p roject n am ele tthe  wiza r d find a nd  ad dall  C++f iles b elowthedi re c tor y
selec t ed " UseVi su al S tud io " for  bui l d,with pr oject typ e " D ynam ic al ly Link ed Library (D LL ) project" 
c hec ked no n e  of thecheckboxes below (ATL,M FC, CLR )
s pecif ied.  dir in t he"Inclu des earchpaths(/I)"  i n D e b ug se t t in gsch ecked "Sam e asDebug  c onfi guratio n" in "Release set t ing s"
clicked Fi nis h bu t t on 

T h is cre at e s c o u ple of VS files  in the di re c to ry:
mylibr a ry. sl n
mylib rary.vc xproj mylibra ry.vcxpro j.filters 
m ylib r a ry. vcxproj.us er

With  a projec t  crea t ed  this  wa y, I p re ssF6 or  selec t  Bu ild |  Rebui ld  solut ion f ro m the me nu.
Then I expect the b uild t o pro duc e the.dll  fi l e s omewhere,  but  it does n otapp ear.Onl y  thes e fi l es  ap p ear:.vs/ m ylibrary/ v 15 /.s u o 
. vs/
 package-install,_instead in_spacemacs you want to_open your.spacemacs_with_SPC f_e_d and add_the package to_your dotspacemacs-additional-packages as such:
dotspacemacs-additional-packages_'(fold-this)

Fold-this is more_straightforward_to setup, because it has less features.
In either case, you'll need to add your_own_keybindings. Or_just_select_the region to fold, and_go SPC SPC fold-this.
If using_vimish-fold, you_need to select the region to fold, and_call_SPC SPC vimish-fold_to fold, and then you can use C-` thereafter_to toggle the fold on and_off. Or call_SPC_SPC_vimish-fold-delete to remove the_fold.

 Q:

Create MS Visual C++ DLL_project out of existing sources

My goal_is to compile existing C++ classes (legacy_code, stored in a set of_*.h files) into a DLL_so that_it can be further integrated_into a C#_application.
For that_purpose, it seems_best to use MS Visual Studio._I have no_experience with this environment, so I_tried_the naive approach_found_on_MSDN and_other SO answers:

File_|_New |_Project_from existing code
selected Visual C++
selected file_location_that is base for include references used_in those.h files
specified a_project_name
let the wizard find_and add all C++ files_below the directory
selected "Use Visual Studio"_for build,_with project_type "Dynamically Linked Library (DLL) project"
checked none of the checkboxes below_(ATL, MFC, CLR)
specified. dir in the_"Include search paths (/I)"_in Debug_settings
checked_"Same as Debug_configuration"_in "Release_settings"
clicked Finish button

This creates couple of VS_files in_the directory:
mylibrary.sln
mylibrary.vcxproj
mylibrary.vcxproj.filters
mylibrary.vcxproj.user

With a project created this_way, I press F6_or_select Build | Rebuild solution from_the menu.
Then I expect the build_to produce the.dll file somewhere,_but_it_does not appear. Only these_files appear:
.vs/mylibrary/v15/.suo
.vs/