javascript - Cannot read property of 'appendchild' of null in a For-Loop -

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i have small database have retrieved data , stored in html table.

this table contains 3 columns , 3 rows.

what want via javascript create div each row, within create div each cell in row of table (to allow me style in css).

i have created number of loops go through , attempt this, problem second loop have created, goes through once , receive error of "cannot read property 'appendchild' of null". not sure why doing this. appreciated.

var gettable = document.getelementbyid('projectstable');  var rowlength = gettable.rows.length;  (i =0; i< rowlength; i++) {     var divname = 'projects' + i;     block = document.createelement('div');     block.id = divname;     document.getelementbyid('javascript').appendchild(block);       var getcells = gettable.rows.item(i).cells;      var celllength = getcells.length;      (var j = 0; j < celllength; j++) {         var divname2 = 'projects' + j;         var projectinfo = 'info' + j;         info = document.createelement('div');         info.id = projectinfo;         document.getelementbyid(divname2).appendchild(info);           var cellval = getcells.item(j).innerhtml;         var getdiv = document.getelementbyid(projectinfo);         getdiv.innerhtml = cellval;      }  }

the first loop creates div whole row , attaches div in page exists, error on 2nd loop.

you using many unnecessary variables , definitions. example divname2 should same divname , redundant. hope example helps out.

<!doctype html> <html>     <head>         <script>             function loadtable(){                 var tt = document.getelementbyid('projectstable'); //source table                 var tj = document.getelementbyid('javascript'); //new clone container                 if (tt && tj){                     for(var i=0, j=tt.rows.length;i<j;i++){                         var tp = document.createelement('div'); //our project div(:=tr)                         tp.id = 'projects' + i.tostring();                          for(k=0, l=tt.rows.item(i).cells.length;k<l;k++){                             var ti = document.createelement('div'); //our info div(:=td)                             ti.id = 'info' + k.tostring();                             ti.innerhtml = (i+1)*k;                             tp.appendchild(ti); //we still have correct project above, use it.                         };                          tj.appendchild(tp); //adding project dom                     };                 };             };         </script>     </head>      <body onload = 'loadtable();'>         <table id = 'projectstable'>             <tr><td>1</td><td>2</td><td>3</td></tr>             <tr><td>4</td><td>5</td><td>6</td></tr>         </table>          <div id = 'javascript'></div>     </body> </html>

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