Example script to loop over all the objects of a ROOT file directory and print in Postscript all the TH1 derived objects. 
This script uses the file generated by tutorial hsimple.C
 
   c1.Print(
"hsimple11.ps[");
 
   for(
auto k : *
f1->GetListOfKeys()) {
 
      c1.Print(
"hsimple11.ps");
 
   }
   c1.Print(
"hsimple11.ps]");
 
}
ROOT::Detail::TRangeCast< T, true > TRangeDynCast
TRangeDynCast is an adapter class that allows the typed iteration through a TCollection.
 
TClass instances represent classes, structs and namespaces in the ROOT type system.
 
Bool_t InheritsFrom(const char *cl) const override
Return kTRUE if this class inherits from a class with name "classname".
 
static TClass * GetClass(const char *name, Bool_t load=kTRUE, Bool_t silent=kFALSE)
Static method returning pointer to TClass of the specified class name.
 
A ROOT file is an on-disk file, usually with extension .root, that stores objects in a file-system-li...
 
static TFile * Open(const char *name, Option_t *option="", const char *ftitle="", Int_t compress=ROOT::RCompressionSetting::EDefaults::kUseCompiledDefault, Int_t netopt=0)
Create / open a file.
 
TH1 is the base class of all histogram classes in ROOT.
 
void Draw(Option_t *option="") override
Draw this histogram with options.
 
Book space in a file, create I/O buffers, to fill them, (un)compress them.
 
T * ReadObject()
To read an object (non deriving from TObject) from the file.
 
virtual const char * GetClassName() const
 
- Author
 - Rene Brun 
 
Definition in file loopdir11.C.