javascript - Uncaught TypeError: courses.splice is not a function -

course_id array contain 1 same value function argument

enter code here function remove_course(course) { var courses=document.getelementsbyname('course_id[]'); var courses=course.value; var index = courses.indexof(course_id); if (index > -1) { courses.splice(index, 1); } } 

here's basic solution, should things done

function remove_course(course) {    //get ellements name, it's nodelist    var element = document.getelementsbyname('course_id[]');        //get first element's value, it's string    var courses_raw= element[0].value;        //convert string valid json object    var courses = json.parse(courses_raw);        //courses array    var index = courses.indexof(course);    if (index > -1) {            //splice      courses.splice(index, 1);            //set value element      element[0].value = json.stringify(courses);    }  }

<input name="course_id[]" value="[1,2,3]" />  <button onclick=remove_course(1)>remove 1</button>  <button onclick=remove_course(2)>remove 2</button>  <button onclick=remove_course(3)>remove 3</button>