加法有問(wèn)題,1+1應(yīng)該等于2,但卻顯示11
<!DOCTYPE html>
<html>
<head>
<title> 事件</title>
<script type="text/javascript">
function count() {
//獲取第一個(gè)輸入框的值
var var1 = document.getElementById("txt1").value;
//獲取第二個(gè)輸入框的值
var var2 = document.getElementById("txt2").value;
//獲取選擇框的值
var select1 = document.getElementById("select").value;
var result = " ";
//獲取通過(guò)下拉框來(lái)選擇的值來(lái)改變加減乘除的運(yùn)算法則
if(select1 == "+"){
result = var1 + var2;
}else?
if(select1 == "-"){
result = var1 - var2;
}else?
if(select1 == "*"){
result = var1 * var2;
}else?
if(select1 == "/"){
result = var1 / var2;
}
//設(shè)置結(jié)果輸入框的值?
// var3 = document.getElementById("");
// fuction add(){
document.getElementById("fruit").value = result;
// }
}
</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()"/>
<!--通過(guò) = 按鈕來(lái)調(diào)用創(chuàng)建的函數(shù),得到結(jié)果-->
<input type='text' id='fruit'/>
</body>
</html>
2023-03-02
我找到問(wèn)題了??