XML Object

This is a code example for using the XML library to convert an XML string to a Lua table and to look through an XML string to find and return a tag or attribute.

Text Controller Setup

Drag in a Text Controller and name it XML. Add four Text Boxes named Input, Output, Find, and Found. (see picture below).

Next, copy the Example Code to the Text Controller.

XML Example Code

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-- Include
require("LuaXML") -- require the LuaXML lib so it can be referenced


-- Aliases
Input = Controls.Input
Output = Controls.Output
Find = Controls.Find
Found = Controls.Found


-- Variables
XML = ""


-- Functions
function EncodeXML()  -- function to encode xml data into a lua table
  if Input.String ~= "" then -- make sure there is input data
    XML = xml.eval(Input.String) -- encode input string to lua table and assign to var XML
    Output.String = tostring(XML) -- convert the XML lua table to a string so it can be read
  end
end

function FindMatch() -- see if a tag or attribute exists in a XML lua table
  if Find.String ~= "" and XML ~= "" then -- make sure the find string and XML var have data
    local found = tostring(xml.find(XML,Find.String)) -- convert the found XML data to a string and assign to var found
    if found == "nil" then -- ensure found has data (nil means could not find string)
      Found.String = "NO MATCH" -- found is nil so no match is printed in the Found textbox
      print("NO MATCH")
    else
      Found.String = found -- found has data (found the string) and print it in the Found textbox
      print("FOUND: "..found)
    end
  end
end

function Initialization() -- first function called on start of the script
  EncodeXML()
  FindMatch()
end


-- EventHandlers
Input.EventHandler = EncodeXML -- call EncodeXML everytime the Input EventHandler is called
Find.EventHandler = FindMatch -- call FindMatch everytime the Find EventHandler is called


-- Start at Runtime
Initialization() -- call this function on the start of the script

Using the Example

In the Options Combo Box, select “Encode” or “Decode”. Enter the XML string into the Input Text Box and the result will populate in the Output Text Box. In the Find Text Box, enter the tag or attribute for which to search the XML string. If found, it populates in the Found Text Box.