Map.exists Method
Determines whether a particular value exists as a key in the map.
Syntax
public boolean exists(anytype keyValue)
Run On
Called
Parameters
- keyValue
Type: anytype
The value for which to check.
Return Value
Type: boolean
true if the specified key value exists in the map; otherwise, false.
Remarks
Use this method to guard calls to the Map.lookup method. If the Map.lookup method does not find the value it is looking for, it throws an exception.
Examples
The following example checks whether a particular style exists in a map of styles in a style sheet. If it does, a new name is substituted for the body style.
static void renameStyle(Map stylesheet, str fromName, str toName)
{
str body;
if (stylesheet.exists(fromName))
{
body = stylesheet.lookup (fromName);
stylesheet.remove (fromName);
stylesheet.insert (toName, body);
}
else
{
info (fromName);
}
}