简单的javascript哪里出错？
<html>
<head>
<title> 标题 </title>
<script language="javascript">
function a()
{
Confirm("是否进行运算！");
var prompt1 = Prompt("请输入一个正整数 n :","50");
if(prompt1 < 0 ){ alert("输入有误！");}
if(prompt1 > 0 ){ b(prompt1);}
}
function b(n)
{
for (int i =0 ; i <= n ; i++)
{
var res = 0;
var ii = i;
while(ii%2==0)
{
res += i;
ii += 1;
}
}
document.form.text.value = res ;
}
}
</script>
</head>
<body>
<form action = "" method = "post" name="form">
<input type="text" name = "text" value = "0" disabled = disabled />
<input type="button" value = "正整数n内的偶数和" name = "button" onClick = "a()"/>
</form>
</body>
</html>
[解决办法]
- HTML code
<html><head><title> 标题 </title><script language="javascript"> function a() { confirm("是否进行运算！"); var prompt1 = prompt("请输入一个正整数 n :","50"); if(prompt1 < 0 ){ alert("输入有误！");} if(prompt1 > 0 ){ b(prompt1);} } function b(n) { for (var i =0 ; i <= n ; i++) { var res = 0; var ii = i; while(ii%2==0) { res += i; ii += 1; } document.form.text.value = res ; }}</script></head><body><form action = "" method = "post" name="form"><input type="text" name = "text" value = "0" disabled = disabled /><input type="button" value = "正整数n内的偶数和" name = "button" onClick = "a()"/></form></body></html>
[解决办法]
Confirm、Prompt 注意大小写
js中变量 用 var来定义
[解决办法]
错得多得去了。。
confirm、prompt 注意大小写
js没有int关键字
逻辑错误- HTML code
<!DOCTYPE html><html><head> <title> 标题 </title> <meta charset="utf-8"/> <script language="javascript"> function a(){ confirm("是否进行运算！"); var prompt1 = prompt("请输入一个正整数 n :","50"); if(prompt1 < 0 ){ alert("输入有误！");} if(prompt1 > 0 ){ b(prompt1);} } function b(n){ var res = 0; for (var i =0 ; i <= n ; i++){ res += i % 2 === 0 && i; } document.form.text.value = res ; } </script></head><body> <form action = "" method = "post" name="form"> <input type="text" name = "text" value = "0" disabled = disabled /> <input type="button" value = "正整数n内的偶数和" name = "button" onClick = "a()"/> </form></body></html>
[解决办法]
错得多得去了。。
1. confirm、prompt 注意大小写
2. js没有int关键字
3. 逻辑错误- HTML code
<!DOCTYPE html><html><head> <title> 标题 </title> <meta charset="utf-8"/> <script type="text/javascript"> function a(){ if(confirm("是否进行运算！")){ var prompt1 = parseInt(prompt("请输入一个正整数 n :","50")); prompt1 > 0 ? b(prompt1) : alert("输入有误！"); } } function b(n){ var res = 0; for (var i =0 ; i <= n ; i++){ res += i % 2 === 0 && i; } document.form.text.value = res ; } </script></head><body> <form action = "" method = "post" name="form"> <input type="text" name = "text" value = "0" disabled = disabled /> <input type="button" value = "正整数n内的偶数和" name = "button" onClick = "a()"/> </form></body></html>