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Index › Programming Questions & Help › Syntax Questions › how do i make loadString use the array i declered

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how do i make loadString use the array i declered (Read 953 times)

yair

how do i make loadString use the array i declered
Mar 6^th, 2010, 6:31am

hi
i seem to have to declare the lines[] array when using loadString,
but if cant call loadString from outside setup. how can use it globaly?
Code:


String lines[] ;
void setup(){
  String lines[] = loadStrings("everyJPG.log");
}
void draw(){
  println("there are " + lines.length + " lines");
}

scope, var, array scope, loadString

yair

Re: how do i make loadString use the array i declered
Reply #1 - Mar 6^th, 2010, 6:39am

obviously wrong? but works

Code:


//String lines[]=new String[99999];
String names[]=new String[99999];

void setup(){

  String lines[] = loadStrings("everyJPG.log");
  arraycopy(lines, names);
  println("there are " + lines.length + " lines");

  noLoop();
}
void draw(){
println("there are " + names.length + " lines");

  for (int i=0; i < names.length; i++) {
    println(names[i]);
  }

}

ChristianT

Re: how do i make loadString use the array i declered
Reply #2 - Mar 6^th, 2010, 8:39am

When you write String lines[], you are creating a new array of Strings named lines. And there can be multiple variables names lines -- in your case one exists globally and one only exists inside setup(), which then "obstructs" the global variable.

Try lines = loadStrings(...) inside setup() of your first post. This way, you are assigning the result of loadStrings(...) to the global variable, rather than to a newly created local one inside setup().

blindfish

Re: how do i make loadString use the array i declered
Reply #3 - Mar 7^th, 2010, 2:41am

To clarify a little further: To declare your array globally you don't have to set its length, which is just as well when you don't already know it; and it avoids the need for this kind of horrible kludge:

Code:

String names[]=new String[99999];

This is really, really inefficient and should be avoided altogether... Instead try:

Code:

// declare array globally
String[] lines;

void setup(){
  // Now it's just a matter of populating it:
  lines = loadStrings("everyJPG.log");
}

void draw(){
  println("there are " + lines.length + " lines");
}

If you want some clarification on variable scope this might be helpful.

Where is the what if the what is in why?

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