faqts : Computers : Programming : Languages : JavaScript : Language Core : Variables

+ Search
Add Entry AlertManage Folder Edit Entry Add page to http://del.icio.us/
Did You Find This Entry Useful?

8 of 11 people (73%) answered Yes
Recently 6 of 8 people (75%) answered Yes

Entry

How do I load variables from a file on the server?

Mar 31st, 2000 10:05
Eddie Shipman, http://wsabstract.com/javatutors/matrixscroll/


I am using the "Dot-Matrix" scroller by Ray M from 
http://wsabstract.com/javatutors/matrixscroll/ on a web page for a
baseball league and want to show the latest scores. But I didn't
want to have to update the entire home page every time I wanted to
change scores. How'd I do it? I placed the scores in a separate
file and called it like this:

*** Here's my scores.js:
var data = "Mets 6-Braves 2  Rangers 5-Devil Rays 2"

*** Here's my HTML file:
<html>
  <head>
    <title>Latest Scores</title>
    <!-- 
         The next line loads the variable "data" with the 
         string I want to use in the scrolling display
    -->
    <script src="scores.js" language="javascript"></script>
    <script language="javascript">
    /*
    Dot Matrix Scroller - by RayM 06-01-00
    For tutorial and full source to script, see 
    http://wsabstract.com/javatutors/matrixscroll/
    */
    
    //specify the directory where the images are in,
    //or leave blank if they are in the same directory as this script.
    //For example, "images/" or "" are both valid values
    var imagepath=""       
    // text string to display loaded from  
    // scores.js                          
    var text=data          
    //  number of display cells
    var nc=8;              
    //  scroll speed in msec (default=130)    
    var spd=130;           
    //  counter for one whole loop (offset loop)
    var count=0;           
    //  starting pos of substring
    var offs=0;            

    //preload images routine (By Wsabstract.com)
    var preloadimages=new Array()
    for (p=32;p<=163;p++){
      preloadimages[p]=new Image()
      preloadimages[p].src=imagepath+"sm"+p+".gif"
    }
    
    //  update scrolling display every 130 msec
    function startscroll() {        
     action=window.setInterval("go()",spd);          
    }

    //  main loop. done every 130 msec    
    function go() {                          
      //  get substring        
      strd=text.substr(offs,(count+1));      
      //  no longer than 21 chars (no. of cells)
      var str=strd.substr(0,nc);                     
      //  if text has reached left side, start chopping off
      if (count>(nc-2) && str.length<nc) {           
        //  how many spaces to add at end, if any
        var se=(nc-len);                             
        while (str.length<nc) {                      
          //  pad out end with spaces         
          str=str+" ";                               
          se+=1;
        }
      }
      //  get length of substring
      len=str.length;                                
      //  counter for display characters sub-loop
      var c=0;                                       
      //  do for all characters in this substring
      while (c<len) {                                
        //  select a single char from this sub-string
        r=str.substr(c,1);                           
        //  get ascii code of this char
        g=r.charCodeAt(0);                           
        chr=eval('document.c'+((nc+1)-len+c)); 
        //  display picture
        chr.src=imagepath+"sm"+g+".gif";             
        //  inc char counter   
        c+=1;                                        
      }
      //  inc this when done one whole loop
      count+=1;                                        
        if (count>=nc) {
        offs+=1;
     }
     //  wrap at end
     if (count>(text.length+(nc-1))) {               
     count=0;
     offs=0;
     }
    }
    
  </script>
  </head>
  <body onload="startscroll()">
    <table cols="8" border="0" cellpadding="0" cellspacing="0"> 
      <tr>
        <td>
          <img src="sm32.gif" width="16" height="22" name="c1">
        </td>
        <td>
          <img src="sm32.gif" width="16" height="22" name="c2">
        </td>
        <td>
          <img src="sm32.gif" width="16" height="22" name="c3">
        </td>
        <td>
          <img src="sm32.gif" width="16" height="22" name="c4">
        </td>
        <td>
          <img src="sm32.gif" width="16" height="22" name="c5">
        </td>
        <td>
          <img src="sm32.gif" width="16" height="22" name="c6">
        </td>
        <td>
          <img src="sm32.gif" width="16" height="22" name="c7">
        </td>
        <td>
          <img src="sm32.gif" width="16" height="22" name="c8">
        </td>
      </tr>
    </table>
  </body>
</html>