Save and load string from text file

I’m trying to use loadString() and saveString() and convert the string to int and the other way around. But I get the errors

"Type mismatch, “java.lang.String[]” does not match with “java.lang.String”

on String loadHighScores = loadStrings(filename1); and

Type mismatch, “java.lang.String” does not match with “java.lang.String[]”

on String saveHighScore[] = str(highScore);

Here is the code:

  String loadHighScores = loadStrings(filename1);
  int highScore = int(loadHighScores);

  String saveHighScore[] = str(highScore);
  saveStrings(filename1, saveHighScore);

Also would this work with processing for Android?

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that as your error says, you need to think in array []

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LoadStrings() and SaveStrings() use arrays of strings, not single strings.

I added [] on

String[] loadHighScores = loadStrings(filename1);
int highScore[] = int(loadHighScores);

but then I get the same error on


and I cant do


How do I fix that?

EDIT: I can fix it with changing the normal int to int []but that wont work with my other code. Can I copy an int to an int[]?

pls use print to see what lines are in your file,
and make loop over all lines.

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I get the error before I run the code. I added an edit “I can fix it with changing the normal int to int []but that wont work with my other code. Can I copy an int to an int[]?”

Would that work?

pls disable “bad” lines, using
// disabled
stay more close to the example from the reference

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I added println(loadHighScores); and it printed what’s in the file. Is that what you meant?

Edit again: Sorry I think I know what you meant. I printed the string and it said “[0]” then what was in the file

and?? you find the line? with the number ?
in the reference they do THIS:

println("there are " + loadHighScores.length + " lines");
for (int i = 0 ; i <loadHighScores.length; i++) {
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int highScore = int(loadHighScores[0]);

might work then

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I got

there are 1 lines

So I added the lines

int i = 0;
  highScore = int(loadHighScores[i]);

the loadString now works. Thank you so much.

Is there anything similar I can do to String saveHighScore[] = str(highScore);?

again see

is again string array string, can not work.

String[] saveHighScore;

might work;

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The saving works, but how do I make an int into a String? only shows for "String"s and not for "String[]"s

Sorry for late reply. Did some testing but I got a NullPointerException on saveHighScore[0]=str(highScore); when I change the value of highScore

try this, but it expects that the file with one line and one number in it already exists.

int myscore = 0;

String filename = "data/scores.txt";     // ! file must exists, have one line with one integer
String[] lines;

void setup() {
  size(200, 200);
  lines = loadStrings(filename);
  println("read scores from "+filename);
  println("got "+lines.length+" lines ");
  for ( int i =0; i<lines.length; i++) println("i "+i+" "+lines[i]);
  myscore = int(lines[0]);
  println("myscore "+myscore);

void draw() {
  myscore = int(random(7, 78));

void keyPressed() {
  if ( key == 's' ) {
    lines[0] = str(myscore);
    println("saved to "+filename);


That worked! Thank you so, so much!!

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A String is a Word or a text.

The [] always indicates that we have an Array of something, a list.

In your case a list of Strings (String[]). For a high score that means, first line in the list is lines[0], 2nd is lines[1] etc., could be Paul 10 in 1st line, Frank 8 in 2nd line. To read all lines, often for-loops are used to loop over the lines in the list.


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