ex01.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<script type="text/javascript">
function fn_click() {
let selected_spans = document.querySelector('#my_span'); //선택자
if (selected_spans.innerText != 'Good Evening') {
selected_spans.innerHTML = 'Good Evening'
}else{
console.log(selected_spans)
selected_spans.innerHTML = 'Good Morning'
}
}
</script>
</head>
<body>
EX01
<br>
<span id="my_span">Good Morning</span>
<input type="button" value="click" onclick="fn_click()">
</body>
</html>
ex02.html
js console 창에서 int => 파란색 , str => 검은색
str => int 변환 : parseInt(str)
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<script type="text/javascript">
function myclick() {
let num =document.querySelector('.it');
console.log(num.value)
let dounum =parseInt(num.value)*2
console.log(dounum)
num.value =dounum
}
</script>
</head>
<body>
EX02 <br>
<input class="it" type="text" value="100">
<input type="button" value="DOUBLE" onclick="myclick()">
</body>
</html>
