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Re: best method to "hide" a whole <table> column ?

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Em 10/12/2013 21:22, Thomas 'PointedEars' Lahn escreveu:
> Denis McMahon wrote:
>
>> function hide(tid,c,h=true){
>                         ^^^^^
> Syntax error.  Default parameters cannot (yet) be defined this way in
> strictly conforming implementations of ECMAScript.  You have to initialize
> them if they are not present, for example:
>
>    function hide(tid, c, h)
>    {
>      if (typeof h == "undefined")
>      {
>        h = true;
>      }

Considering your "strictly conforming implementations of ECMAScript", 
it could be just:

   if (h === undefined) { h = true; }

or

   h = h || true;

>
>      /* or */
>
>      if (arguments.length < 3)
>      {
>        h = true;
>      }
>
> The difference between the first and second approach is that with the second
> one there is no false positive if “undefined” is passed for “h”.

It's not the case, but there is a problem with this sort of testing when 
an optional argument is passed a value from another source such as a 
configuration object, when it might produce undefined. That's why it is 
better to test for undefined.

>
>>    var i,t=document.getElementById(tid);
>>    for(i=0;i<t.rows.length;i++)
>>      t.rows[i].cells[c-1].style.display=h?"none":"table-cell";
>
>      t.rows[i].cells[c-1].style.display = h ? "none" : "";
>
> Setting the value of a style property to the empty string resets it to its
> initial value.
>

Good catch.


-- 
Joao Rodrigues (J.R.)

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Re: best method to "hide" a whole <table> column ? kumarcherukuris@gmail.com - 2013-12-10 09:02 -0800
  Re: best method to "hide" a whole <table> column ? Denis McMahon <denismfmcmahon@gmail.com> - 2013-12-10 19:20 +0000
  Re: best method to "hide" a whole <table> column ? Denis McMahon <denismfmcmahon@gmail.com> - 2013-12-10 20:31 +0000
    Re: best method to "hide" a whole <table> column ? "Evertjan." <exjxw.hannivoort@interxnl.net> - 2013-12-10 22:35 +0000
      Re: best method to "hide" a whole <table> column ? Denis McMahon <denismfmcmahon@gmail.com> - 2013-12-11 00:16 +0000
      Re: best method to "hide" a whole <table> column ? Hans-Georg Michna <hans-georgNoEmailPlease@michna.com> - 2013-12-11 11:16 +0100
        Re: best method to "hide" a whole <table> column ? Nisse Engström <news.NOSPAM.uvex6@luden.se> - 2014-02-15 02:38 +0100
      Re: best method to "hide" a whole <table> column ? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2013-12-11 11:23 -0200
        Re: best method to "hide" a whole <table> column ? Denis McMahon <denismfmcmahon@gmail.com> - 2013-12-11 19:16 +0000
    Re: best method to "hide" a whole <table> column ? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-12-11 00:22 +0100
      Re: best method to "hide" a whole <table> column ? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2013-12-11 14:36 -0200
        Re: best method to "hide" a whole <table> column ? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-12-11 18:27 +0100
        Re: best method to "hide" a whole <table> column ? Denis McMahon <denismfmcmahon@gmail.com> - 2013-12-11 19:23 +0000
          Re: best method to "hide" a whole <table> column ? Joao Rodrigues <groups_jr-1@yahoo.com.br> - 2013-12-11 22:08 -0200

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