Duplicate values in drop down list box

Collapse
This topic is closed.
X
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • marx
    #1

    Duplicate values in drop down list box

    I have a bit of a problem and any help would be much appreciated.

    Problem: I have two dropdown list boxes with same data(all data
    driven).
    These are used for two separate entries.
    For every entry you cannot choose the same value twice.
    For example, I cannot choose for entry 1 the same
    value in both selection boxes (gqCategory1Ent ry1 and
    gqCategory2Entr y1)

    This part works.
    The second entry is the problem: When I choose a value for Entry
    Two that is the same as in entry one it thinks that "Dubplicate
    Divisons have been selected").

    WHen in fact these are two separate entries.

    Code:
    <head>
    //Enry number one...no Duplicates
    function check_selection (elt){
    //check for duplicate selections
    var form=elt.form;
    var name=elt.name;
    var index=elt.selec tedIndex
    //loop through all form elements
    for(var i=0;i<form.leng th;i++){
    var_name=form.e lements[i].name;
    var_index=form. elements[i].selectedIndex;
    if(var_name.sub string(0,16)!=' gqCategory'){
    // if form element is not the current element
    // and the division name is the same, raise
    //error message
    if(var_name!=na me&&index!=0&&v ar_index==index ){
    alert(var_name) ;
    alert("Duplicat e divisions selected! Please choose again.");
    elt.selectedInd ex=0;
    elt.focus();
    return false;
    }
    }
    }
    return true;
    }


    </head>

    Entry one:
    <select name="gqCategor y1Entry1" maxlength="48" tabindex = 20
    onChange="check _selection(this )" maxlength="48">
    <option value="-1"> ---Select a Category---
    <option value=1.1 > Division - 1.1 - Internet Sites
    <option value=1.2 > Division - 1.2 - Intranet Sites
    <option value=1.3 > Division - 1.3 - Interactive communication
    </select>
    <select name="gqCategor y2Entry1" maxlength="48" tabindex = 20
    onChange="check _selection(this )" maxlength="48">
    <option value="-1"> ---Select a Category---
    <option value=1.1 > Division - 1.1 - Internet Sites
    <option value=1.2 > Division - 1.2 - Intranet Sites
    <option value=1.3 > Division - 1.3 - Interactive communication
    </select>
    ------------
    Entry TWO:
    <select name="gqCategor y1Entry2" maxlength="48" tabindex = 20
    onChange="check _selection(this )" maxlength="48">
    <option value="-1"> ---Select a Category---
    <option value=1.1 > Division - 1.1 - Internet Sites
    <option value=1.2 > Division - 1.2 - Intranet Sites
    <option value=1.3 > Division - 1.3 - Interactive communication
    </select>
    <select name="gqCategor y2Entry2" maxlength="48" tabindex = 20
    onChange="check _selection(this )" maxlength="48">
    <option value="-1"> ---Select a Category---
    <option value=1.1 > Division - 1.1 - Internet Sites
    <option value=1.2 > Division - 1.2 - Intranet Sites
    <option value=1.3 > Division - 1.3 - Interactive communication
    </select>
    Tags: None
    • Lasse Reichstein Nielsen
      #2
      Re: Duplicate values in drop down list box

      marx@idiom.com (marx) writes:
      [color=blue]
      > I have a bit of a problem and any help would be much appreciated.
      >
      > Problem: I have two dropdown list boxes with same data(all data
      > driven).[/color]

      You have two select elements with identical options.
      [color=blue]
      > These are used for two separate entries.[/color]

      I.e., you have *four* select elements with identical options,
      grouped into two "entries".
      [color=blue]
      > For every entry you cannot choose the same value twice.
      > For example, I cannot choose for entry 1 the same
      > value in both selection boxes (gqCategory1Ent ry1 and
      > gqCategory2Entr y1)
      >
      > This part works.
      > The second entry is the problem: When I choose a value for Entry
      > Two that is the same as in entry one it thinks that "Dubplicate
      > Divisons have been selected").[/color]

      So the code checks all select elements, not only the ones in the same
      "entry".
      [color=blue]
      > WHen in fact these are two separate entries.
      >
      > Code:
      > <head>
      > //Enry number one...no Duplicates
      > function check_selection (elt){
      > //check for duplicate selections
      > var form=elt.form;
      > var name=elt.name;
      > var index=elt.selec tedIndex
      > //loop through all form elements
      > for(var i=0;i<form.leng th;i++){
      > var_name=form.e lements[i].name;
      > var_index=form. elements[i].selectedIndex;[/color]

      These variables are not declared, so they become global variables.
      No need for that. Put a "var" in front.
      [color=blue]
      > if(var_name.sub string(0,16)!=' gqCategory'){[/color]

      You only check that they have the same first 16 characters. That misses
      the distinction between entries, which is much later in the name.

      Example names:
      gqCategory1Entr y2
      gqCategory1Entr y1

      The entry number is past the first 16 characters, and is never checked.

      In case you ever need more than 9 or 10 categories or entries, let's
      make this work for any number:

      ---
      function check_selection (elt){
      var gqCategoryRE = /^gqCategory(\d+ )Entry(\d+)$/;
      var index = elt.selectedInd ex;
      if (index == 0) {return true;} // always legal
      var match = elt.name.match( gqCategoryRE);
      if (!match) { return; } // not a gqCategory at all.
      var category = +match[1];
      var entry = +match[2];

      var elems = elt.form.elemen ts;
      for (var i=0;i<elems.len gth;i++) {
      if (elems[i] == elt) {continue;} // don't test self
      match=elems[i].name.match(gqC ategoryRE);
      if ( match && entry == +match[2] && // same entry
      index == elems[i].selectedIndex) { // same selectedIndex
      alert("Duplicat e division selected! Please choose again.");
      elt.selectedInd ex = 0;
      elt.focus(0);
      return false;
      }
      }
      return true;
      }
      ---

      Tested in Opera 7 with the supplied select elements.
      /L
      --
      Lasse Reichstein Nielsen - lrn@hotpop.com
      DHTML Death Colors: <URL:http://www.infimum.dk/HTML/rasterTriangleD OM.html>
      'Faith without judgement merely degrades the spirit divine.'

        Comment

        Previous template Next
        Working...