救救孩纸吧(2)

源自：6-11 编程练习

救救孩纸吧(2)

<!DOCTYPE html>

<html>

<head>

function count(){

var one=document.getElementById("txt1").value; one=parseInt(one);

var two=document.getElementById("txt2").value;

twe=parseInt(twe);

var a=doucument.getElementById("select").value;

var num;

switch(a){

case "+":

num=one+two;

break;

case "-":

num=one-two;

break;

case "*":

num=one*two;

break;

case "/" :

num=one/two;

break;

}

document.getElementById("fruit").value=num;

} </script>

</head>

<body>

</select>

</body></html>

提问者：摸一哈 2020-03-10 14:25

个回答

weixin_慕妹4115393

2020-03-14 22:24:23

<!DOCTYPE html>
<html>
<head>
<title> 事件</title>
<script type="text/javascript">
function count(){
var txt1=document.getElementById("txt1").value;
var txt2=document.getElementById("txt2").value;
var select=document.getElementById("select").value;
//获取第一个输入框的值
//获取第二个输入框的值
//获取选择框的值
//获取通过下拉框来选择的值来改变加减乘除的运算法则
//设置结果输入框的值
var sum;
switch(select){
case"+":
sum=parseInt(txt1)+parseInt(txt2);
break;
case'-':
sum=parseInt(txt1)-parseInt(txt2);
break;
case'*':
sum=parseInt(txt1)*parseInt(txt2);
break;
case'/':
sum=parseInt(txt1)/parseInt(txt2);
break;
}
document.getElementById("fruit").value=sum;
}
</script>
</head>
<body>
<input type='text' id='txt1' />
<select id='select'>
<option value='+'>+</option>
<option value="-">-</option>
<option value="*">*</option>
<option value="/">/</option>
</select>
<input type='text' id='txt2' />
<input type='button' value=' = ' onclick="count()"/> 
<input type='text' id='fruit'>
</body>
</html>

0
摸一哈

2020-03-11 14:27:52

<!DOCTYPE html>
改成这样：
<html>
<head>
<title> 事件</title>
<script type="text/javascript">
function count(){
var one=document.getElementById("txt1").value; one=parseInt(one);
var two=document.getElementById("txt2").value;
two=parseInt(twe);
var a=document.getElementById("select").value;
var num;
switch(a){
case "+":
num=one+two;
break;
case "-":
num=one-two;
break;
case "*":
num=one*two;
break;
case "/" :
num=one/two;
break;
}
document.getElementById("fruit").value=num;
} </script>
</head>
<body>
<input type='text' id='txt1' />
<select id='select'>
<option value="+">+</option>
<option value="-">-</option>
<option value="*">*</option>
<option value="/">/</option>
</select>
<input type='text' id='txt2' />
<input type='button' value=' = ' onclick="count()" /> 
<input type='text' id='fruit' />
</body></html>

0
浮木Elvis

2020-03-11 13:31:33

<!DOCTYPE html>
<html>
<head>
    <title> 事件</title>
    <script type="text/javascript">
        function count() {
            var one = parseInt( document.getElementById("txt1").value);
            var two = parseInt( document.getElementById("txt2").value);
            var a = document.getElementById("select").value;
            var num;
            switch (a) {
                case "+":
                    num = one + two;
                    break;
                case "-":
                    num = one - two;
                    break;
                case "*":
                    num = one * two;
                    break;
                case "/":
                    num = one / two;
                    break;
            }
            document.getElementById("fruit").value = num;
        }
    </script>
</head>
<body>
    <input type='text' id='txt1' />
    <select id='select'>
        <option value='+'>+</option>
        <option value="-">-</option>
        <option value="*">*</option>
        <option value="/">/</option>
    </select>
    <input type='text' id='txt2' />
    <input type='button' value=' = ' onclick="count()" />
    
    <input type='text' id='fruit' />
</body>
</html>

var two=document.getElementById("txt2").value;
twe=parseInt(twe);
            上面一句的 twe = parseInt(twe)改成 var two = parseInt(two)
var a=doucument.getElementById("select").value; //这一句的document 拼写错了

0