无法使用javascript和jquery创建下拉框

Question

I have the following code:

for (i = 0; i < 13; i++){
    $('.players').append('<div class="rule_dropdown"><select name="rule' + i + '">');
    for(j = 0; j < rules.length; j++){
        $('.players').append('<option>' + rules[j] + '</option>');
    }
    $('.players').append('</select></div>');

}

I want to have 13 dropdown lists with the same content. I expect this to happen:

1. First for loop add an opening div and select
2. For each rule in rules array, append an option
3. Add closing select and closing div
4. Go back to #1

But this is what actually happens:

1. First loop add opening AND closing div and select.
2. Second loop add option with the right content

Does anyone know why?

Answer 1

I think append adds a full element to the DOM rather than just adding the text into the HTML as it were. Try building up your elements individually and adding them a bit like this:

for (i = 0; i < 13; i++){
  var $select = $('<select name="rule' + i + '"></select>');
  for(j = 0; j < rules.length; j++) {
    $select.append('<option>' + rules[j] + '</option>');
  }
  var $div = '<div class="rule_dropdown"></div>';
  $div.append($select);
  $('.players').append($div);
}

Answer 2

From the documentation:

The .append() method inserts the specified content as the last child of each element in the jQuery collection.

The options you want to add should be the child elements of the select, not the div.

Answer 3

I think this is what you want to do..

var rules=[1,2,3,4,5,6];
    for (i = 0; i < 13; i++){
    $('.players').append('<div class="rule_dropdown"><select id="rule'+ i +'" name="rule' + i + '">');
    for(j = 0; j < rules.length; j++){
        $('#rule'+i).append('<option>' + rules[j] + '</option>');
    }
    $('.players').append('</select></div>');

}