Text Parsing Tutorial

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Tutorials

Introduction

Parsing text is where you seperate the elements and nodes from the values. Say I had this single line of string

String = "5,100,4,5|10,100,3,2|"

Parsing it would seperate each value from each. But for now, were sticking with seperating from the |'s and not the ,'s

We want it to seperate into this: 5,100,4,5 10,100,3,2

Creating the script

First off, lets establish our variables.

LastKey = 0 -- This is needed for the ParseText [[function]]
AllStrings = {} -- Were all strings will be put into

Ok, we have our variables. Let's get to work on the function.

function ParseText(String,EndKey)
StrLength = #String
PLength = #EndKey
   for i=1, StrLength do
      if string.sub(String,i,i) == EndKey then -- This right here is detecting the letter/symbol/number on that line
         if LastKey == 0 then -- Checking to see see if a "|" was found already. This will be needed for the next function
            LastKey = i + 1 -- Setting the LastKey to the current key
         end
      end
   end
end

Okay, now we need the ReplaceString fuction. This will be to remove the "|"'s from the string.

function ReplaceString(String,Replace,ReplaceKey) 
String = tostring(String)
A,B = string.find(String,Replace) -- Finding if there really is a key to be replaced and finding the character number.
NewString = string.sub(String,1,A-1)..ReplaceKey..string.sub(tostring(String),B+1,String:len()) -- Replacing the "|" with ""
return NewString
end

Now we need to add it all together and add to the ParseText function

LastKey = 0 -- This is needed for the ParseText function
AllStrings = {} -- Were all strings will be put into

function ReplaceString(String,Replace,ReplaceKey) 
String = tostring(String)
A,B = string.find(String,Replace) -- Finding if there really is a key to be replaced and finding the character number.
NewString = string.sub(String,1,A-1)..ReplaceKey..string.sub(tostring(String),B+1,String:len()) -- Replacing the "|" with ""
return NewString
end

function ParseText(String,EndKey)
StrLength = #String
PLength = #EndKey
   for i=1, StrLength do
      if string.sub(String,i,i) == EndKey then -- This right here is detecting the letter/symbol/number on that line
         if LastKey == 0 then -- Checking to see see if a "|" was found already. This will be needed for the next function
            table.insert(AllStrings,ReplaceString(string.sub(String,1,i),EndKey,"")) -- Inserts the string into a table :D
            LastKey = i + 1 -- Setting the LastKey to the current key
         else
            table.insert(AllStrings,ReplaceString(string.sub(String,LastKey,i),EndKey,""))-- Inserts the string into the table
            --[[This is were the LastKey was needed. If we wouldnt of had the last key and used 1 instead, it would of returned the whole string because of string.sub. The last key in this string in the first case that the "else" has been called would be 5 + 1 which is |]]
         end
      end
   end
end

Now all they are seperated into all values for each, player or whatever your storing per |. You could use the same ParseText function on the ","'s.

Time to print each result

ParseText("5,100,4,5|10,100,3,2|","|")
for i,v in pairs(AllStrings) do
print(v)
end 

See also

• String manipulation
• Table manipulation
• Tables