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hash_map::empty (STL/CLR)

 

The latest version of this topic can be found at hash_map::empty (STL/CLR).

Tests whether no elements are present.

Syntax

bool empty();  

Remarks

The member function returns true for an empty controlled sequence. It is equivalent to hash_map::size (STL/CLR)() == 0. You use it to test whether the hash_map is empty.

Example

// cliext_hash_map_empty.cpp   
// compile with: /clr   
#include <cliext/hash_map>   
  
typedef cliext::hash_map<wchar_t, int> Myhash_map;   
int main()   
    {   
    Myhash_map c1;   
    c1.insert(Myhash_map::make_value(L'a', 1));   
    c1.insert(Myhash_map::make_value(L'b', 2));   
    c1.insert(Myhash_map::make_value(L'c', 3));   
  
// display contents " [a 1] [b 2] [c 3]"   
    for each (Myhash_map::value_type elem in c1)   
        System::Console::Write(" [{0} {1}]", elem->first, elem->second);   
    System::Console::WriteLine();   
    System::Console::WriteLine("size() = {0}", c1.size());   
    System::Console::WriteLine("empty() = {0}", c1.empty());   
  
// clear the container and reinspect   
    c1.clear();   
    System::Console::WriteLine("size() = {0}", c1.size());   
    System::Console::WriteLine("empty() = {0}", c1.empty());   
    return (0);   
    }  
  
 [a 1] [b 2] [c 3]  
size
() = 3  
empty
() = False  
size
() = 0  
empty
() = True  

Requirements

Header: <cliext/hash_map>

Namespace: cliext

See Also

hash_map (STL/CLR)
hash_map::size (STL/CLR)