# JS syntax - dictionaries [[JS Syntax]] ### dictionaries Constructing a dictionary ```js var dict = { Key1: "Value1", Key2: "Value2", } ``` Adding a new entry (key-value pair) ```js dict["Key3"] = "Value3" ``` Updating an existing value ```js dict["Key1"] = "NewValue1" dict.Key1 = "NewNewValue1" ``` Adding to an existing value ```js dict["Key2"].push("AnotherValue2") ``` Using a list as a dictionary value ```js dict["Key4"] = [] ``` Appending to an existing value (*that is a list*) ``` dict.Key4.push("Value4") dict.Key4.push("Value5","Value6") ``` #### test/example code block ```dataviewjs const dict = { Key1: "Value1", Key2: "Value2", } dict["Key1"] = "NewValue1"; dict.Key1 = "NewNewValue1" dict["Key3"] = "Value3"; dict["Key4"] = [] dict["Key4"].push("Value4"); dict["Key4"].push("Value5","Value6"); dv.paragraph(dict) ```