Javascript Addition wont work -

Can anyone tell me how to add these variables:

  var preciopag = Document valores.T1.value; Var libraz = document.valores.T2.value; Var ServicesOcom = 5.00 var contador1 = 0; Var contador2 = 0; Var tramite = 0; Var angioptis = 0; Var ITBMS = 0; Var Total = Presoep + ServicioCom + NVPT + Tramite + ITBMS;  

Thanks in advance.

values ​​ elements always had a string , Therefore, + will result in concatenation , not except that

String number to get value:

  var preciopag = + document.valores.T1.value; Var libras = + document.valores.T2.value;  

I used + , which will look at the whole string, but you can see the parseFloat which will ignore anything Lastly invalid; It is entirely dependent on what you want to do with semi-valid input.

Display:

  var preciopag = "5"; // Simulate the document. Original. T. 1.value var libras = "10"; // Simulate the document. Differentiation. 2.value var serviciocom = 5.00 var contador1 = 0; Var contador2 = 0; Var tramite = 0; Var angioptis = 0; Var ITBMS = 0; Var Total = Presoep + ServicioCom + NVPT + Tramite + ITBMS; Snippet.log (total); // "55000" - wrong // instead: preciopag = + "5"; // Simulate the document. Original. T. 1.value libras = + "10"; // Simulate the document. Differentiation. 2.value total = presoepag + servercom.c + angiopet + tramite + ITbms; Snippet.log (total); // "10" - Correct  

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