Problems with counter

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Problems with counter

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#1 by (2 votes)

0

I have the following counter:

It is inside a table in which foods are selected through a checkbox; So, its function is to calculate the sum of the kcal of the foods that are selected.

The problem is that it is used in several sections of the same page and it started with the addition of the previous checkbox. Therefore, I tried to improve it with the properties of the javascript objects, hence caloriasT ['name']. The problem is that it returns 'NaN'. Where this error? Thank you!

caloriasT={};

function contador(checkbox,kcal,nombre) {
   var sum=parseFloat(kcal);
   if($(checkbox).is(":checked")){
      caloriasT['nombre']+=sum;
   }else{
      caloriasT['nombre']-=sum;
   }
   $("#"+nombre).html(Math.abs(caloriasT['nombre']).toFixed(2)+'&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Kcals');
}

javascript jquery

asked by Roledi 01.07.2017 в 19:51

source

1 answer

Using INNER JOINs with USING, ON or WHERE (where tabla.column) Error when selecting data from the database with ajax [closed]

score 2 · Accepted Answer

The main problem is that you add a value to a variable that still has no defined value (no, the variables are not initialized to 0 , its initial value is undefined ) so you should add:

if (typeof caloriasT[nombre] === 'undefined') {
    caloriasT[nombre] = 0;
}

before adding or subtracting anything. link

Apart from that, you're using the 'nombre' tag instead of the nombre parameter everywhere, but that's an autoforma.