how to get value from select without refresh?

0
votes

I made a CGPA-SGPA calculator and I cannot get the value with refresh. When I refresh and check the value it get feed but not getting value without refresh.

var credit_1001 = document.querySelector('#credit_1001')
var grade_1001 = document.querySelector('#grade_1001')
var credit_1002 = document.querySelector('#credit_1002')
var grade_1002 = document.querySelector('#grade_1002')
var credit_1003 = document.querySelector('#credit_1003')
var grade_1003 = document.querySelector('#grade_1003')
var credit_1004 = document.querySelector('#credit_1004')
var grade_1004 = document.querySelector('#grade_1004')
var credit_1008 = document.querySelector('#credit_1008')
var grade_1008 = document.querySelector('#grade_1008')
var credit_1009 = document.querySelector('#credit_1009')
var grade_1009 = document.querySelector('#grade_1009')
//btn and result S1
var btn_check = document.querySelector('#check_s1')
var result_s1 = document.querySelector('#result_s1')

//btn click S1
var total_s1_credit = parseInt(credit_1001.value) + parseInt(credit_1002.value) + parseInt(credit_1003.value) + parseInt(credit_1004.value) + parseInt(credit_1008.value) + parseInt(credit_1009.value)
var got_s1_marks = parseInt(credit_1001.value) * parseInt(grade_1001.value) + parseInt(credit_1002.value) * parseInt(grade_1002.value) + parseInt(credit_1003.value) * parseInt(grade_1003.value) + parseInt(credit_1004.value) * parseInt(grade_1004.value) + parseInt(credit_1008.value) * parseInt(grade_1008.value) + parseInt(credit_1009.value) * parseInt(grade_1009.value)
btn_check.addEventListener('click', () => {

    result_s1.innerText = " S1 SGPA " + got_s1_marks / total_s1_credit
    console.log("S1 Total Credit = " + total_s1_credit)
    console.log("S1 Got Marks = " + got_s1_marks)
    console.log("S1 SGPA = " + result_s1.innerText)
})
javascripthtmlselect