www.webdeveloper.com
Results 1 to 10 of 10

Thread: Problem with variable

  1. #1
    Join Date
    Jul 2006
    Location
    Sweden
    Posts
    190

    Problem with variable

    Hi!

    function BytBild2(number) {
    test = "bild" + number.toString();

    document.getElementById("storbild").src="bilder/bilder_stora/" + test + ".jpg";

    This dosen't work! But if I write bild2, then it works! How come it dosen't work and what do I do wrong? What I'm trying to do is to concatenating different parts to a variable. bild2 ha a value from the beginning. And I just wanted to save a lot of code to put bild + number and use just one line of code instead of several?!

    Appreciate som help! Thanks!
    Last edited by pkng; 06-11-2010 at 03:49 PM.

  2. #2
    Join Date
    Aug 2007
    Posts
    3,767
    How do you call it?

    And there is no need to call toString. This will do.
    Code:
    function BytBild2(number) {
    test = "bild" + number;
    document.getElementById("storbild").src="bilder/bilder_stora/" + test + ".jpg";
    }
    BytBild2(2);
    Great wit and madness are near allied, and fine a line their bounds divide.

  3. #3
    Join Date
    Jul 2006
    Location
    Sweden
    Posts
    190
    Thanks! But are you sure it works? I have tried this several times! I'm unsure if it's possible to create a new variable named 'test' by concatenating bild + 1 which already is a variable name, 'bild1', with a value of 0011_1. I can't get this value to the new variable 'test'!?

    I call it like BytBild2(2); but as I wrote variables 'bild1' to 'bild5' are already declared variables with different values before I call BytBild2(2);
    My thought was to just use less amount of lines of code and create a new variable instead of

    if (number == 1) {
    document.getElementById("storbild").src="bilder/bilder_stora/" +bild1+ ".jpg";} bild1 could have the value of 0004_2

    ......

    if (number == 5) {
    document.getElementById("storbild").src="bilder/bilder_stora/" +bild5+ ".jpg";} bild5 could have the value of 0015_5


    What I wanted was just this few lines:

    function BytBild2(3) {
    test = ???? + number
    document.getElementById("storbild").src="bilder/bilder_stora/" + test + ".jpg";
    }

    Do you understand how I mean?
    Last edited by pkng; 06-11-2010 at 05:32 PM.

  4. #4
    Join Date
    Jan 2010
    Posts
    77
    Hi bud

    I think your problem is that you forgot to declare your "test" variable
    Code:
       test = "bild"+ number
    should be
    Code:
       var test = "bild"+ number
    That said, if it were me I wouldnt bother with the "test" variable
    Code:
      function ByBild2(number){
        document.getElementById("storbild").src="bilder/bilder_stora/bild" + number + ".jpg"; 
                            }
    V

  5. #5
    Join Date
    Jul 2006
    Location
    Sweden
    Posts
    190
    Hi!

    It's not necessary to declare a variable in java script. And if you declare the variable inside a function it gets local scope and will not be global!

    I'm trying to create a string, I'm trying to create a new variable and assign a value to it, but guess it's impossible!?

  6. #6
    Join Date
    Apr 2003
    Location
    Netherlands
    Posts
    21,654
    Code:
    var test = window["bild" + number];
    At least 98% of internet users' DNA is identical to that of chimpanzees

  7. #7
    Join Date
    Jul 2006
    Location
    Sweden
    Posts
    190

    Question

    Sorry, but it doesn't work!

    var number = 2;
    var test = window["bild_" + number];

    if I also add an Alert I get a message saying 'undefined' and after some time. Seems like browser locks!?

    ?

  8. #8
    Join Date
    Aug 2007
    Posts
    3,767
    I know for absolute sure, guaranteed, that this will do what I say it does.
    Code:
    function function BytBild2(number) {
    alert("bilder/bilder_stora/bild" + number + ".jpg");
    }
    BytBild2(2);
    That code will alert "bilder/bilder_stora/bild2.jpg". If not, you have problems elsewhere in your code. Guaranteed.
    Great wit and madness are near allied, and fine a line their bounds divide.

  9. #9
    Join Date
    Apr 2003
    Location
    Netherlands
    Posts
    21,654
    which already is a variable name, 'bild1', with a value of 0011_1. I can't get this value to the new variable 'test'!?
    Like this?
    Code:
    function BytBild2(number) {
    var test = window["bild" + number];
    document.getElementById("storbild").src="bilder/bilder_stora/" + test + ".jpg";
    }
    var bild1 = '0011_1';
    BytBild2(1);
    At least 98% of internet users' DNA is identical to that of chimpanzees

  10. #10
    Join Date
    Jul 2007
    Posts
    386
    Guys, what he wants is to create a variable name from string to read its value. Something by the like of the following in PHP:

    Code:
    <?php
        $blid1 ='test'; 
        $num = 1;
        $test = ${'blid'.$num};
        
        echo $test;
    ?>
    Edit:
    Fang's proposal is a nice work around. Try that.
    Last edited by SparoHawk; 06-12-2010 at 10:27 AM.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
HTML5 Development Center



Recent Articles