In Lua, you can replace a substring within a string using the string.gsub() function.
The syntax of the function is as follows:
string.gsub(mainString, pattern, replacementString, [maxReplacements])
- mainString is the original string that you want to modify
- pattern is the substring that you want to replace
- replacementString is the new substring that will replace the pattern
- maxReplacements (optional) is the maximum number of replacements you want to make. If not specified, all occurrences of the pattern will be replaced.
Here's an example:
local myString = "The quick brown fox jumps over the lazy dog"
local newString = string.gsub(myString, "fox", "kangaroo")
print(newString) -- The quick brown kangaroo jumps over the lazy dog
In this example, the string.gsub() function is used to replace "fox" with "kangaroo" in myString. The resulting string, "The quick brown kangaroo jumps over the lazy dog", is stored in newString.
You can also use regular expressions to match more complex patterns. Here's an example:
local date = "Today is 01/01/2022"
local newDate = string.gsub(date, "%d+/%d+/%d+", "tomorrow")
print(newDate) -- Today is tomorrow
In this example, the %d+/%d+/%d+ pattern matches a date in the format "dd/mm/yyyy" (where dd, mm, and yyyy are numbers), and replaces it with the string "tomorrow". The resulting string, "Today is tomorrow", is stored in newDate.