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-   -   Radio & Checkbox & Drop Down values (http://www.codingforums.com/showthread.php?t=284151)

jmrker 12-14-2012 06:32 PM
Radio & Checkbox & Drop Down values
 
Continuation of a resolved thread: http://www.codingforums.com/showthread.php?t=284053

I tried making a test HTML for 'OldPedant's post #5 in the referenced link above.
In the process, I tried using the same type of logic to a single & multiple select box.

It seems to work, but I would like an evaluation of the logic for the 'getSelectValue()' function.

Is it a good way to perform the checks?
Was/is there a way to use the original 'getGroupValue()' function with the D-Downs in one common function?

Code:
<!DOCTYPE HTML>
<html>
<head>
<title> CBox/RBtn Tests </title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>

<body>
<form id="myForm" action="" method="post" onsubmit="return false">
<table border="1">
 <tr>
  <td valign="top"> CBox<br>
  <input type="checkbox" name="cbox" id="cb0" value="0"> 0<br>
  <input type="checkbox" name="cbox" id="cb1" value="1"> 1<br>
  <input type="checkbox" name="cbox" id="cb2" value="2"> 2<br>
  <input type="checkbox" name="cbox" id="cb3" value="3"> 3<br>
  <input type="checkbox" name="cbox" id="cb4" value="4"> 4
  </td>
  <td valign="top"> RBtn<br>
  <input type="radio" name="rbtn" value="A"> A<br>
  <input type="radio" name="rbtn" value="B"> B<br>
  <input type="radio" name="rbtn" value="C"> C<br>
  <input type="radio" name="rbtn" value="D"> D<br>
  <input type="radio" name="rbtn" value="E"> E
  </td>
  <td valign="top"> Single CBox<br>
  <input type="checkbox" name="cboxAgree" id="cbAgree" value="cbAgree"> CBox Agree
  </td>
  <td valign="top"> Single RBtn<br>
  <input type="radio" name="rbtnAgree" value="rbAgree"> RBtn Agree<br>Kinda Silly
  </td>

  <td valign="top">  Single DD<br>Selection<br>
  <select id="sboxS" name="sboxS">
    <option value="">Choose One</option>
    <option value="0">0</option>
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option>
  </select>
  </td>
  <td valign="top"> Multiple DD<br>Selection<br>
  <select id="sboxM" name="sboxM" multiple>
    <option value="">Choose One Or More</option>
    <option value="a">a</option>
    <option value="b">b</option>
    <option value="c">c</option>
    <option value="d">d</option>
    <option value="e">e</option>
  </select>
  </td>
 </tr>
</table> <p> <button onclick="statusDisplay()">Status Report</button>
</form>

<script type="text/javascript">

// Following from: http://www.codingforums.com/showthread.php?t=284053
function getGroupValue( group ) {
    if ( group == null ) { return null; } // OMIT this if you know there is at least one
// handle the case of only one item in the "group"
    if ( group.length == null ) { return group.checked ? [ group.value ] : null; }

    var allchecked = [ ];
    for ( var g = 0; g < group.length; ++g ) {
        if ( group[g].checked ) { allchecked.push( group[g].value ); }
    }
    return allchecked.length > 0 ? allchecked : null;
}

// Modified from above for Drop-Down Selections (single and multiple)
function getSelectValue( group ) {
    if ( group == null ) { return null; } // OMIT this if you know there is at least one
// handle the case of only one item in the "group"
    if ( group.options.length == null ) {
      return (group.selectedIndex != -1) ? [ group.options[group.selectedIndex].value ] : null; }

    var allchecked = [ ];
    for ( var g = 0; g < group.options.length; ++g ) {
        if ( group.options[g].selected ) { allchecked.push( group.options[g].value ); }
    }
    return allchecked.length > 0 ? allchecked : null;
}

function statusDisplay() {
  var frm = document.getElementById('myForm');
  var cb = getGroupValue(frm.cbox);
  var rb = getGroupValue(frm.rbtn);
  var cbA = getGroupValue(frm.cboxAgree);
  var rbA = getGroupValue(frm.rbtnAgree);
  var sbS = getSelectValue(frm.sboxS);
  var sbM = getSelectValue(frm.sboxM);
  var str = 'cbox: '+cb+'\n\nrbtn: '+rb+'\n\nsingle cbox: '+cbA+'\n\nsingle rbtn: '+rbA
          + '\n\nsingle select: '+sbS+'\n\nmultiple select: '+sbM;
  alert(str);
}
</script>

</body>
</html>

AndrewGSW 12-14-2012 06:35 PM
I'll follow you to this post then..
I would correct the HTML at the beginning (in particular, to prevent IE dropping into quirks mode) so that it can be tested in all browsers:

Code:
<!DOCTYPE html>
<html>
<head>
<title> CBox/RBtn Tests </title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
Just my personal opinion/preference but I would return the value false rather than null. I might use null if a function is expected to return an object.

Seems to work well. Again, just my personal opinion :), but I would prefer to use separate functions. I think these are trying to do too much, and if I look at this again in a couple of months I'll need to remind myself of what the functions do. Of course, function documentation (docstrings) would help with this.

jmrker 12-14-2012 06:50 PM
Recommended modifications
 
Here I have incorporated your recommendations, if of interest to anyone else...
Code:
<!DOCTYPE HTML>
<html>
<head>
<title> CBox/RBtn/SBox Tests </title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>

<body>
<form id="myForm" action="" method="post" onsubmit="return false">
<table border="1">
 <tr>
  <td valign="top"> CBox<br>
  <input type="checkbox" name="cbox" id="cb0" value="cb-0"> 0<br>
  <input type="checkbox" name="cbox" id="cb1" value="cb-1"> 1<br>
  <input type="checkbox" name="cbox" id="cb2" value="cb-2"> 2<br>
  <input type="checkbox" name="cbox" id="cb3" value="cb-3"> 3<br>
  <input type="checkbox" name="cbox" id="cb4" value="cb-4"> 4
  </td>
  <td valign="top"> RBtn<br>
  <input type="radio" name="rbtn" value="rb-A"> A<br>
  <input type="radio" name="rbtn" value="rb-B"> B<br>
  <input type="radio" name="rbtn" value="rb-C"> C<br>
  <input type="radio" name="rbtn" value="rb-D"> D<br>
  <input type="radio" name="rbtn" value="rb-E"> E
  </td>
  <td valign="top"> Single CBox<br>
  <input type="checkbox" name="cboxAgree" id="cbAgree" value="cbAgree"> CBox Agree
  </td>
  <td valign="top"> Single RBtn<br>
  <input type="radio" name="rbtnAgree" value="rbAgree"> RBtn Agree<br>Kinda Silly
  </td>

  <td valign="top">  Single DD<br>Selection<br>
  <select id="sboxS" name="sboxS">
    <option value="">Choose One</option>
    <option value="ssb-0">0</option>
    <option value="ssb-1">1</option>
    <option value="ssb-2">2</option>
    <option value="ssb-3">3</option>
    <option value="ssb-4">4</option>
  </select>
  </td>
  <td valign="top"> Multiple DD<br>Selection<br>
  <select id="sboxM" name="sboxM" multiple>
    <option value="">Choose One Or More</option>
    <option value="msb-A">a</option>
    <option value="msb-B">b</option>
    <option value="mab-C">c</option>
    <option value="msb-D">d</option>
    <option value="msh-E">e</option>
  </select>
  </td>
 </tr>
</table> <p> <button onclick="statusDisplay()">Status Report</button>
</form>

<script type="text/javascript">

// Following from: http://www.codingforums.com/showthread.php?t=284053
function getGroupValue( group ) {
    if ( group == null ) { return false; } // OMIT this if you know there is at least one
// handle the case of only one item in the "group"
    if ( group.length == null ) { return group.checked ? [ group.value ] : false; }
//  if ( group.length == null ) { return group.checked ? [ 0 ] : false; }  // to return position, instead of value

    var allchecked = [ ];
    for ( var g = 0; g < group.length; ++g ) {
        if ( group[g].checked ) { allchecked.push( group[g].value ); }
//      if ( group[g].checked ) { allchecked.push( g ); }  // to return position, instead of value, of selections
    }
    return allchecked.length > 0 ? allchecked : false;
}

// Modified from above for Drop-Down Selections (single and multiple)
function getSelectValue( group ) {
    if ( group == null ) { return false; } // OMIT this if you know there is at least one
// handle the case of no items in the "group"
    if ( group.options.length == null ) {
        return (group.selectedIndex != -1) ? [ group.options[group.selectedIndex].value ] : false;
        return (group.selectedIndex != -1) ? [ group.selectedIndex ] : false;  // to return position, instead of value
    }

    var allchecked = [ ];
    for ( var g = 0; g < group.options.length; ++g ) {
        if ( group.options[g].selected ) { allchecked.push( group.options[g].value ); }
//      if ( group.options[g].selected ) { allchecked.push( g ); }  // to return position, instead of value, of selections
    }
    return allchecked.length > 0 ? allchecked : false;
}

function statusDisplay() {
  var frm = document.getElementById('myForm');
  var cb = getGroupValue(frm.cbox);
  var rb = getGroupValue(frm.rbtn);
  var cbA = getGroupValue(frm.cboxAgree);
  var rbA = getGroupValue(frm.rbtnAgree);
  var sbS = getSelectValue(frm.sboxS);
  var sbM = getSelectValue(frm.sboxM);
  var str = 'cbox: '+cb+'\n\nrbtn: '+rb+'\n\nsingle cbox: '+cbA+'\n\nsingle rbtn: '+rbA
          + '\n\nsingle select: '+sbS+'\n\nmultiple select: '+sbM;
  alert(str);
}
</script>

</body>
</html>

AndrewGSW 12-14-2012 07:52 PM
It is a shame we can't convert a nodeList into an array with [group], so I think I've just wasted 30 minutes:

Code:
    var arr = [];
    for (var i = group.length; i--; arr.unshift(group[i]));
    return arr.map(function (obj) {
        return (obj.checked) ? obj.value : false;
    }).filter(function (obj) {
        return (obj !== false);
    });
..but exploring JavaScript is never really a waste of time :)

jmrker 12-15-2012 03:28 AM
Quote:
Originally Posted by AndrewGSW (Post 1299934)
It is a shame we can't convert a nodeList into an array with [group], so I think I've just wasted 30 minutes:

Code:
    var arr = [];
    for (var i = group.length; i--; arr.unshift(group[i]));
    return arr.map(function (obj) {
        return (obj.checked) ? obj.value : false;
    }).filter(function (obj) {
        return (obj !== false);
    });
..but exploring JavaScript is never really a waste of time :)
That is a quite interesting piece of code.
I won't pretend I understand it all, but it does appear to work as the earlier script
EXCEPT for the single checkbox or radio button option.
Since I believe they would be seldom used that way, and could easily be checked with ID assignments rather than groups,
I'll demonstrate what the changes would look like.
Code:
<!DOCTYPE HTML>
<html>
<head>
<title> CBox/RBtn/SBox/Multi-SBox Tests </title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>

<body>
<form id="myForm" action="" method="post" onsubmit="return false">
<table border="1">
 <tr>
  <td valign="top"> CBox<br>
  <input type="checkbox" name="cbox" id="cb0" value="cb-0"> 0<br>
  <input type="checkbox" name="cbox" id="cb1" value="cb-1"> 1<br>
  <input type="checkbox" name="cbox" id="cb2" value="cb-2"> 2<br>
  <input type="checkbox" name="cbox" id="cb3" value="cb-3"> 3<br>
  <input type="checkbox" name="cbox" id="cb4" value="cb-4"> 4
  </td>
  <td valign="top"> RBtn<br>
  <input type="radio" name="rbtn" value="rb-A"> A<br>
  <input type="radio" name="rbtn" value="rb-B"> B<br>
  <input type="radio" name="rbtn" value="rb-C"> C<br>
  <input type="radio" name="rbtn" value="rb-D"> D<br>
  <input type="radio" name="rbtn" value="rb-E"> E
  </td>
  <td valign="top"> Single CBox<br>
  <input type="checkbox" name="cboxAgree" id="cbAgree" value="cbAgree"> CBox Agree
  </td>
  <td valign="top"> Single RBtn<br>
  <input type="radio" name="rbtnAgree" value="rbAgree"> RBtn Agree<br>Kinda Silly
  </td>

  <td valign="top">  Single DD<br>Selection<br>
  <select id="sboxS" name="sboxS">
    <option value="">Choose One</option>
    <option value="ssb-0">0</option>
    <option value="ssb-1">1</option>
    <option value="ssb-2">2</option>
    <option value="ssb-3">3</option>
    <option value="ssb-4">4</option>
  </select>
  </td>
  <td valign="top"> Multiple DD<br>Selection<br>
  <select id="sboxM" name="sboxM" multiple>
    <option value="">Choose One Or More</option>
    <option value="msb-A">a</option>
    <option value="msb-B">b</option>
    <option value="mab-C">c</option>
    <option value="msb-D">d</option>
    <option value="msh-E">e</option>
  </select>
  </td>
 </tr>
</table>
<p> <button onclick="statusDisplay()">Status Report</button>
<button onclick="altStatusDisplay()">Alternate Status Report</button>
</form>

<script type="text/javascript">

// Following from: http://www.codingforums.com/showthread.php?t=284053
function getGroupValue( group ) {
    if ( group == null ) { return false; } // OMIT this if you know there is at least one
// handle the case of only one item in the "group"
    if ( group.length == null ) { return group.checked ? [ group.value ] : false; }
//  if ( group.length == null ) { return group.checked ? [ 0 ] : false; }  // to return position, instead of value

    var allchecked = [ ];
    for ( var g = 0; g < group.length; ++g ) {
        if ( group[g].checked ) { allchecked.push( group[g].value ); }
//      if ( group[g].checked ) { allchecked.push( g ); }  // to return position, instead of value, of selections
    }
    return allchecked.length > 0 ? allchecked : false;
}

// Modified from above for Drop-Down Selections (single and multiple)
function getSelectValue( group ) {
    if ( group == null ) { return false; } // OMIT this if you know there is at least one
// handle the case of no items in the "group"
    if ( group.options.length == null ) {
        return (group.selectedIndex != -1) ? [ group.options[group.selectedIndex].value ] : false;
//      return (group.selectedIndex != -1) ? [ group.selectedIndex ] : false;  // to return position, instead of value
    }

    var allchecked = [ ];
    for ( var g = 0; g < group.options.length; ++g ) {
        if ( group.options[g].selected ) { allchecked.push( group.options[g].value ); }
//      if ( group.options[g].selected ) { allchecked.push( g ); }  // to return position, instead of value, of selections
    }
    return allchecked.length > 0 ? allchecked : false;
}

function statusDisplay() {
  var frm = document.getElementById('myForm');
  var cb = getGroupValue(frm.cbox);
  var rb = getGroupValue(frm.rbtn);
  var cbA = getGroupValue(frm.cboxAgree);
  var rbA = getGroupValue(frm.rbtnAgree);
  var sbS = getSelectValue(frm.sboxS);
  var sbM = getSelectValue(frm.sboxM);
  var str = 'cbox: '+cb+'\n\nrbtn: '+rb+'\n\nsingle cbox: '+cbA+'\n\nsingle rbtn: '+rbA
          + '\n\nsingle select: '+sbS+'\n\nmultiple select:\n'+sbM;
  alert(str);
}

/* ----------------------Alternative script-------------------------------------------------- */
function altStatusDisplay() {
  var frm = document.getElementById('myForm');
  var cb = getGroupChecks(frm.cbox);
  var rb = getGroupChecks(frm.rbtn);
  var cbA = getGroupChecks(frm.cboxAgree);  // does not handle single checkboxes
  var rbA = getGroupChecks(frm.rbtnAgree);  // does not handle single radio buttons
  var sbS = getSelectOptions(frm.sboxS);
  var sbM = getSelectOptions(frm.sboxM);
  var str = 'cbox: '+cb+'\n\nrbtn: '+rb+'\n\nsingle cbox: '+cbA+'\n\nsingle rbtn: '+rbA
          + '\n\nsingle select: '+sbS+'\n\nmultiple select:\n'+sbM;
  alert(str);
}

// Missing some single button status reports
//  Does NOT handle single group selections
function getGroupChecks(group) {
    var arr = [];
    for (var i = group.length; i--; arr.unshift(group[i]));
    return arr.map(function (obj) {
        return (obj.checked) ? obj.value : false;
    }).filter(function (obj) {
        return (obj !== false);
    });
}

function getSelectOptions(group) {
    var arr = [];
    for (var i = group.length; i--; arr.unshift(group[i]));
    return arr.map(function (obj) {
        return (obj.selected) ? obj.value : false;
    }).filter(function (obj) {
        return (obj !== false);
    });
}
/* ------------------------------------------------------------------------ */

</script>

</body>
</html>
Thanks again for the comments and thoughts 'AndrewGSW'
Do you think it relevant enough to put into the 'Post A Javascript' section?

Logic Ali 12-15-2012 05:00 AM
Quote:
Originally Posted by jmrker (Post 1299908)
Was/is there a way to use the original 'getGroupValue()' function with the D-Downs in one common function?
Code:
function getGroupValue( group ) /* group == radio/checkbox single/group or <select> options list */
{
  var selectedElems = [],
      g;
 
  if( group.length === undefined )
  {
    if( group.checked || group.selected )
      selectedElems.push( group.value );
  }
  else
    for( g = 0; group[ g ]; ++g )
      if( group[ g ].checked || group[ g ].selected )
        selectedElems.push( group[ g ].value );
 
  return selectedElems.length > 0 ? selectedElems : null;
}

AndrewGSW 12-15-2012 12:46 PM
Quote:
Do you think it relevant enough to put into the 'Post A Javascript' section?
Up to you, although Logic Ali may have trumped you ;)
Code:
    var arr = [];
    for (var i = group.length; i--; arr.unshift(group[i]));
    return arr.map(function (obj) {
        return (obj.checked) ? obj.value : false;
    }).filter(function (obj) {
        return (obj !== false);
    });
I'm not suggesting this should be incorporated - there is no added value, I was just experimenting :thumbsup:.

A DOM nodeList is like an array but is not an array - it's really a collection of objects. This code first stores (converts?) the nodeList to an array.

The array map method creates another array by applying a function to every element of an array. In this instance, the new array contains either the value false, or the value of the input; that is, if it is checked.

The method filter is then applied to the resultant array. This removes the false elements from the array, leaving only the values of those elements which were checked.

It is not really useful for this example. It could be useful if a lot more processing is done within the map or filter methods. Andy.

jmrker 12-15-2012 04:00 PM
Quote:
Originally Posted by logic ali (Post 1300017)
Code:
function getGroupValue( group ) /* group == radio/checkbox single/group or <select> options list */
{
  var selectedElems = [],
      g;
 
  if( group.length === undefined )
  {
    if( group.checked || group.selected )
      selectedElems.push( group.value );
  }
  else
    for( g = 0; group[ g ]; ++g )
      if( group[ g ].checked || group[ g ].selected )
        selectedElems.push( group[ g ].value );
 
  return selectedElems.length > 0 ? selectedElems : null;
}
wow!!!
I like the idea of one function to collect information from different element types.
Less typing, less prone to errors, common implementation, understandable and neat all rolled-up into one small package.
Thanks for the attention to the topic, 'Logic Ali'.

Added to the "Post A JavaScript" section of this forum. See: http://www.codingforums.com/showthre...64#post1300264


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