How to remove a lua table entry by its key?

In Lua, deleting entries from a table can be achieved by setting the value of the entry to nil. This removes the key-value pair, meaning the key no longer exists in the table. Below, I will introduce the specific steps and provide an example to demonstrate how to delete entries from a table.

Steps

1. Determine the key to delete: First, identify which key you want to remove from the table.
2. Set the value of the key to nil: By setting the value of the key to nil, Lua's garbage collection mechanism automatically removes the key, thereby deleting the key and its corresponding value from the table.

Example

Assume we have the following Lua table:

lua
local fruits = {
    apple = 2,
    banana = 3,
    cherry = 5
}

If you want to delete the entry corresponding to the key banana, you can do the following:

lua
fruits["banana"] = nil  -- Set the value of banana to nil, thereby deleting the entry

After deletion, verify the contents of the fruits table:

lua
for k, v in pairs(fruits) do
    print(k, v)
end

The output will only include apple and cherry, confirming that banana has been deleted.

This method is simple and effective, and it is the standard approach for deleting table entries in Lua.