从数据库表获取价值进入选择框

Question

im creating a combo box which gets value from mysql database table. here is a sample code which im implementing but it will not populates selectbox values.

 mydata +='<div class="content  nodisplay"><div class="row"><div class="label" style="font-size:22px;">Subject</div><div class="data">
<select id="fillsubject" name="fillsubject">';
$.post(document.URL,qstring,function(data){

        var subjects =  $(data).filter('.subjects');

        $.each(subjects,function(index,value){
            var subid = $(this).attr('id');
            var subname = $(this).text();
            mydata += "<option value='"+subid+"'>"+subname+"</option>";
            //mydata += "<option value='english'>english</option>";
        });

});
mydata +='</select></div></div></div>';     

Answer 1

var mydata +='<div class="content  nodisplay"><div class="row"><div class="label" style="font-size:22px;">Subject</div><div class="data"><select id="fillsubject" name="fillsubject"></select></div></div></div>';
$.post(document.URL,qstring,function(data){

        var subjects =  $(data).filter('.subjects');
        var subopts = '';
        $.each(subjects,function(index,value){
            var subid = $(this).attr('id');
            var subname = $(this).text();
            subopts += "<option value='"+subid+"'>"+subname+"</option>";
        });
        //after the loop is over building your <options/> inject the html
        $('#fillsubject').html(subopts);
});

You are splitting the <select></select> that's not necessary. You can do it as above.

Answer 2

How does the code sample fit into the rest of your source code?

Rather than using

mydata += "<option value='"+subid+"'>"+subname+"</option>";

in your .each function, you would be better off using

$("#fillsubject").append("<option value='"+subid+"'>"+subname+"</option>");

I don't know what you're doing with mydata after the code sample you post, but since .post is asynchronous, mydata may have already been displayed to the user when your js gets the reply from your server. If this is the case, then the suggestion above will work as expected.