mappingGetKey()

Returns the key with a specified index.

Synopsis

<type> mappingGetKey(mapping m, int idx);

Parameters

Parameters Meaning
m Mapping
idx The index of the key that should be returned.

Return value

Key of a mapping

Error

Description

Returns the key with the specified index. Mappings save arbitrary key and value pairs. The keys and values are saved in two arrays (one for keys and one for values). A mapping with key:value pairs "one": 1, "two":2, "three":3 looks internally as follows:

key value

"one" 1

"two" 2

"three" 3

The values for the keys are searched via the keys. The keys can be of an arbitrary type and the types can be mixed (so that not only one type is used). If you want to find the value for the key "one", the position of the key "one" will be searched in the key array and the value at this position in the value array will be returned.

Example

main()
{
  int i;
  mapping m;
  m["one"]=1;//sets the value to 1
  m["two"]=2;//sets the value to 2
  DebugN("The value of m[one]is="+m["one"], "the value should
  be=1");
  DebugN("The value of m[two]is="+m["two"], "the value should
  be=2");
  i = m["one"];//sets i to the value of "one"
  DebugN("i is="+i, "i should be =1");
  for (int i = 1; i <= mappinglen(m); i++)
  DebugN("mappingGetKey", i, "is="+mappingGetKey(m, i));
}

Assignment

Miscellaneous functions (mapping)

Availability

CTRL, UI