jquery-traversing: select -> option -> text
I want to compare a variable with a select -> option -> text selected in order to change the "selected" attrib, here is my code, it works but I think is not the best way to write it, excuse my English, I used google translate for help hehehehe :
var lista = 'example 1';
$("#id option").each(function(){
if($(this).text() == lista){
$(this).attr('selected','selected');
}
});
here's the html:
<select i开发者_JAVA技巧d="id" >
<option value="0" >example 1</option>
<option value="1" >example 2</option>
</select>
here's a few attempts
$('#id option:eq("'+lista+'")').attr('selected','selected')
$("#id option[text='"+lista+"']").attr('selected','selected')
Instead of looping through each, you can try this:
var lista = 'example 1';
$('#id option:contains(' + lista + ')').attr('selected', true);
or
$('#id option:[text="' + lista + '"]').attr('selected', true);
Works just as well. It just depends if your variable lista
will need to be an exact match or just a partial one.
There's nothing wrong with what you have, jQuery will be doing more-or-less the same under the hood.
You could use filter()
if you want to chain it all together:
var lista = 'example 1';
$('#id option').filter(function () {
return $(this).text() == lista;
})[0].selected = true;
:contains
might work for you but it works like a wildcard match, e.g. cat would match category:
var lista = 'example 1';
$('#id option:contains(' + lista + ')')[0].selected = true;
Your way is pretty efficient, but could be made a little more so like this:
var lista = 'example 1';
$("#id option").each(function(){
if( this.text == lista ){
this.selected = true;
return false;
}
});
This uses native properties so it will be faster.
.text
property gives the text content of the<option>
element.selected
sets the selected propertyreturn false;
will break the loop once one is selected, so it doesn't needlessly continue
This should work:
$("#id option").attr('selected', function() {
return this.innerHTML === lista;
});
I'm probably too late.
var lista = 'example 1';
$('#id option[text="' + lista + '"]').attr('selected', true);
This is about 97% faster then
var lista = 'example 1';
$('#id option:contains("' + lista + '")').attr('selected', true);
check performance log at http://jsperf.com/selector-performance-00000
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