么小么
2015-05-27 11:33
<!DOCTYPE html>
<html>
<head>
<title> 事件</title>
<script type="text/javascript">
function count(){
//获取第一个输入框的值
var num1=document.getElementById("txt1").value;
//获取第二个输入框的值
var num2=document.getElementById("txt2").value;
var num3=document.getElementById("select").value;
var num4:
//获取选择框的值
switch(num3){
case "+":num4=parseInt(num1)+parseInt(num2);break;
case "-":num4=parseInt(num1)-parseInt(num2);break;
case "*":num4=parseInt(num1)*parseInt(num2);break;
case "/":num4=parseInt(num1)/parseInt(num2);break;
}
document.getElementById("fruit")=num4;
}
</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=' = ' onclik="count()"/> <!--通过 = 按钮来调用创建的函数,得到结果-->
<input type='text' id='fruit' />
</body>
</html>
<!DOCTYPE html> <html> <head> <title> 事件</title> <meta http-equiv="Content-Type" content="text/html;charset=UTF-8"> <script type="text/javascript"> function count(){ /** 获取ID的值 */ var num1 = document.getElementById("txt1").value; var num2 = document.getElementById("txt2").value; var num3 = document.getElementById("select").value; var num4 = ""; /*进行判断运算*/ switch(num3) { case "+": num4 = parseInt(num1) + parseInt(num2); break; case "-": num4 = parseInt(num1) - parseInt(num2); break; case "*": num4 = parseInt(num1) * parseInt(num2); break; case "/": num4 = parseInt(num1) / parseInt(num2); default: alert("Are you kidding me!!!"); } //得到的结果反馈给fruit,也就是value..在页面看到结果 document.getElementById("fruit").value = num4; } </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() /> <!--通过 = 按钮来调用创建的函数,得到结果--> <input type='text' id='fruit' /> </body> </html>
var num4;后面那个符号我改过来了 还是不行
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