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Dictionary¶

A built-in data structure that holds key-value pairs.

Description¶

Dictionaries are associative containers that contain values referenced by unique keys. Dictionaries will preserve the insertion order when adding new entries. In other programming languages, this data structure is often referred to as a hash map or an associative array.

You can define a dictionary by placing a comma-separated list of key: value pairs inside curly braces {}.

Creating a dictionary:

var my_dict = {} # Creates an empty dictionary.

var dict_variable_key = "Another key name"
var dict_variable_value = "value2"
var another_dict = {
    "Some key name": "value1",
    dict_variable_key: dict_variable_value,
}

var points_dict = {"White": 50, "Yellow": 75, "Orange": 100}

# Alternative Lua-style syntax.
# Doesn't require quotes around keys, but only string constants can be used as key names.
# Additionally, key names must start with a letter or an underscore.
# Here, `some_key` is a string literal, not a variable!
another_dict = {
    some_key = 42,
}

var myDict = new Redot.Collections.Dictionary(); // Creates an empty dictionary.
var pointsDict = new Redot.Collections.Dictionary
{
    {"White", 50},
    {"Yellow", 75},
    {"Orange", 100}
};

You can access a dictionary's value by referencing its corresponding key. In the above example, points_dict["White"] will return 50. You can also write points_dict.White, which is equivalent. However, you'll have to use the bracket syntax if the key you're accessing the dictionary with isn't a fixed string (such as a number or variable).

@export_enum("White", "Yellow", "Orange") var my_color: String
var points_dict = {"White": 50, "Yellow": 75, "Orange": 100}
func _ready():
    # We can't use dot syntax here as `my_color` is a variable.
    var points = points_dict[my_color]

[Export(PropertyHint.Enum, "White,Yellow,Orange")]
public string MyColor { get; set; }
private Redot.Collections.Dictionary _pointsDict = new Redot.Collections.Dictionary
{
    {"White", 50},
    {"Yellow", 75},
    {"Orange", 100}
};

public override void _Ready()
{
    int points = (int)_pointsDict[MyColor];
}

In the above code, points will be assigned the value that is paired with the appropriate color selected in my_color.

Dictionaries can contain more complex data:

var my_dict = {
    "First Array": [1, 2, 3, 4] # Assigns an Array to a String key.
}

var myDict = new Redot.Collections.Dictionary
{
    {"First Array", new Redot.Collections.Array{1, 2, 3, 4}}
};

To add a key to an existing dictionary, access it like an existing key and assign to it:

var points_dict = {"White": 50, "Yellow": 75, "Orange": 100}
points_dict["Blue"] = 150 # Add "Blue" as a key and assign 150 as its value.

var pointsDict = new Redot.Collections.Dictionary
{
    {"White", 50},
    {"Yellow", 75},
    {"Orange", 100}
};
pointsDict["Blue"] = 150; // Add "Blue" as a key and assign 150 as its value.

Finally, dictionaries can contain different types of keys and values in the same dictionary:

# This is a valid dictionary.
# To access the string "Nested value" below, use `my_dict.sub_dict.sub_key` or `my_dict["sub_dict"]["sub_key"]`.
# Indexing styles can be mixed and matched depending on your needs.
var my_dict = {
    "String Key": 5,
    4: [1, 2, 3],
    7: "Hello",
    "sub_dict": {"sub_key": "Nested value"},
}

// This is a valid dictionary.
// To access the string "Nested value" below, use `((Godot.Collections.Dictionary)myDict["sub_dict"])["sub_key"]`.
var myDict = new Redot.Collections.Dictionary {
    {"String Key", 5},
    {4, new Redot.Collections.Array{1,2,3}},
    {7, "Hello"},
    {"sub_dict", new Redot.Collections.Dictionary{{"sub_key", "Nested value"}}}
};

The keys of a dictionary can be iterated with the for keyword:

var groceries = {"Orange": 20, "Apple": 2, "Banana": 4}
for fruit in groceries:
    var amount = groceries[fruit]

var groceries = new Redot.Collections.Dictionary{{"Orange", 20}, {"Apple", 2}, {"Banana", 4}};
foreach (var (fruit, amount) in groceries)
{
    // `fruit` is the key, `amount` is the value.
}

Note: Dictionaries are always passed by reference. To get a copy of a dictionary which can be modified independently of the original dictionary, use duplicate.

Note: Erasing elements while iterating over dictionaries is not supported and will result in unpredictable behavior.

Note

There are notable differences when using this API with C#. See C# API differences to GDScript for more information.

Tutorials¶

Constructors¶

Dictionary	Dictionary()
Dictionary	Dictionary(from: Dictionary)

Methods¶

void	clear()
Dictionary	duplicate(deep: bool = false) const
bool	erase(key: Variant)
Variant	find_key(value: Variant) const
Variant	get(key: Variant, default: Variant = null) const
Variant	get_or_add(key: Variant, default: Variant = null)
bool	has(key: Variant) const
bool	has_all(keys: Array) const
int	hash() const
bool	is_empty() const
bool	is_read_only() const
Array	keys() const
void	make_read_only()
void	merge(dictionary: Dictionary, overwrite: bool = false)
Dictionary	merged(dictionary: Dictionary, overwrite: bool = false) const
bool	recursive_equal(dictionary: Dictionary, recursion_count: int) const
int	size() const
Array	values() const

Operators¶

bool	operator !=(right: Dictionary)
bool	operator ==(right: Dictionary)
Variant	operator [](key: Variant)

Constructor Descriptions¶

Dictionary Dictionary() 🔗

Constructs an empty Dictionary.

Dictionary Dictionary(from: Dictionary)

Returns the same dictionary as from. If you need a copy of the dictionary, use duplicate.

Method Descriptions¶

void clear() 🔗

Clears the dictionary, removing all entries from it.

Dictionary duplicate(deep: bool = false) const 🔗

Creates and returns a new copy of the dictionary. If deep is true, inner Dictionary and Array keys and values are also copied, recursively.

bool erase(key: Variant) 🔗

Removes the dictionary entry by key, if it exists. Returns true if the given key existed in the dictionary, otherwise false.

Note: Do not erase entries while iterating over the dictionary. You can iterate over the keys array instead.

Variant find_key(value: Variant) const 🔗

Finds and returns the first key whose associated value is equal to value, or null if it is not found.

Note: null is also a valid key. If inside the dictionary, find_key may give misleading results.

Variant get(key: Variant, default: Variant = null) const 🔗

Returns the corresponding value for the given key in the dictionary. If the key does not exist, returns default, or null if the parameter is omitted.

Variant get_or_add(key: Variant, default: Variant = null) 🔗

Gets a value and ensures the key is set. If the key exists in the dictionary, this behaves like get. Otherwise, the default value is inserted into the dictionary and returned.

bool has(key: Variant) const 🔗

Returns true if the dictionary contains an entry with the given key.

var my_dict = {
    "Redot" : 4,
    210 : null,
}

print(my_dict.has("Redot")) # Prints true
print(my_dict.has(210))     # Prints true
print(my_dict.has(4))       # Prints false

var myDict = new Redot.Collections.Dictionary
{
    { "Redot", 4 },
    { 210, default },
};

GD.Print(myDict.ContainsKey("Redot")); // Prints true
GD.Print(myDict.ContainsKey(210));     // Prints true
GD.Print(myDict.ContainsKey(4));       // Prints false

In GDScript, this is equivalent to the in operator:

if "Redot" in {"Redot": 4}:
    print("The key is here!") # Will be printed.

Note: This method returns true as long as the key exists, even if its corresponding value is null.

bool has_all(keys: Array) const 🔗

Returns true if the dictionary contains all keys in the given keys array.

var data = {"width" : 10, "height" : 20}
data.has_all(["height", "width"]) # Returns true

int hash() const 🔗

Returns a hashed 32-bit integer value representing the dictionary contents.

var dict1 = {"A": 10, "B": 2}
var dict2 = {"A": 10, "B": 2}

print(dict1.hash() == dict2.hash()) # Prints true

var dict1 = new Redot.Collections.Dictionary{{"A", 10}, {"B", 2}};
var dict2 = new Redot.Collections.Dictionary{{"A", 10}, {"B", 2}};

// Redot.Collections.Dictionary has no Hash() method. Use GD.Hash() instead.
GD.Print(GD.Hash(dict1) == GD.Hash(dict2)); // Prints true

Note: Dictionaries with the same entries but in a different order will not have the same hash.

Note: Dictionaries with equal hash values are not guaranteed to be the same, because of hash collisions. On the contrary, dictionaries with different hash values are guaranteed to be different.

bool is_empty() const 🔗

Returns true if the dictionary is empty (its size is 0). See also size.

bool is_read_only() const 🔗

Returns true if the dictionary is read-only. See make_read_only. Dictionaries are automatically read-only if declared with const keyword.

Array keys() const 🔗

Returns the list of keys in the dictionary.

void make_read_only() 🔗

Makes the dictionary read-only, i.e. disables modification of the dictionary's contents. Does not apply to nested content, e.g. content of nested dictionaries.

void merge(dictionary: Dictionary, overwrite: bool = false) 🔗

Adds entries from dictionary to this dictionary. By default, duplicate keys are not copied over, unless overwrite is true.

var dict = { "item": "sword", "quantity": 2 }
var other_dict = { "quantity": 15, "color": "silver" }

# Overwriting of existing keys is disabled by default.
dict.merge(other_dict)
print(dict)  # { "item": "sword", "quantity": 2, "color": "silver" }

# With overwriting of existing keys enabled.
dict.merge(other_dict, true)
print(dict)  # { "item": "sword", "quantity": 15, "color": "silver" }

var dict = new Redot.Collections.Dictionary
{
    ["item"] = "sword",
    ["quantity"] = 2,
};

var otherDict = new Redot.Collections.Dictionary
{
    ["quantity"] = 15,
    ["color"] = "silver",
};

// Overwriting of existing keys is disabled by default.
dict.Merge(otherDict);
GD.Print(dict); // { "item": "sword", "quantity": 2, "color": "silver" }

// With overwriting of existing keys enabled.
dict.Merge(otherDict, true);
GD.Print(dict); // { "item": "sword", "quantity": 15, "color": "silver" }

Note: merge is not recursive. Nested dictionaries are considered as keys that can be overwritten or not depending on the value of overwrite, but they will never be merged together.

Dictionary merged(dictionary: Dictionary, overwrite: bool = false) const 🔗

Returns a copy of this dictionary merged with the other dictionary. By default, duplicate keys are not copied over, unless overwrite is true. See also merge.

This method is useful for quickly making dictionaries with default values:

var base = { "fruit": "apple", "vegetable": "potato" }
var extra = { "fruit": "orange", "dressing": "vinegar" }
# Prints { "fruit": "orange", "vegetable": "potato", "dressing": "vinegar" }
print(extra.merged(base))
# Prints { "fruit": "apple", "vegetable": "potato", "dressing": "vinegar" }
print(extra.merged(base, true))

bool recursive_equal(dictionary: Dictionary, recursion_count: int) const 🔗

Returns true if the two dictionaries contain the same keys and values, inner Dictionary and Array keys and values are compared recursively.

int size() const 🔗

Returns the number of entries in the dictionary. Empty dictionaries ({ }) always return 0. See also is_empty.

Array values() const 🔗

Returns the list of values in this dictionary.

Operator Descriptions¶

bool operator !=(right: Dictionary) 🔗

Returns true if the two dictionaries do not contain the same keys and values.

bool operator ==(right: Dictionary) 🔗

Returns true if the two dictionaries contain the same keys and values. The order of the entries does not matter.

Note: In C#, by convention, this operator compares by reference. If you need to compare by value, iterate over both dictionaries.

Variant operator [](key: Variant) 🔗

Returns the corresponding value for the given key in the dictionary. If the entry does not exist, fails and returns null. For safe access, use get or has.