我是新來的html5和javascript,並且正在使用html5和javascript編寫一個簡單的表單。當我按netbeans運行時,表單按預期顯示在chromo上,但是當我輸入兩個數字並按add時,而不是在結果列中顯示3
,而是顯示[object HTMLInputElement][object HTMLInputElement]
。HTML5表單顯示[對象HTMLInputElement] [對象HTMLInputElement]而不是實際結果添加兩個數字
可能有人請告訴我爲什麼發生這種情況?我該如何解決這個錯誤?
<html>
<head>
<title>TODO supply a title</title>
<link rel="shortcut icon" href=""><!--this is to be removed for production code, its been placed here because otherwise netbeans produce error message-->
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<script type="text/javascript">
function addTwoNumbers() {
var firstNumber = document.getElementById("txtFirstNumber").valueOf();
var secondNumber = document.getElementById("txtSecondNumber").valueOf();
document.getElementById("txtResult").value = firstNumber + secondNumber;
}
</script>
</head>
<body>
<form>
First number<br>
<input type="text" ID="txtFirstNumber"><br>
Second number<br>
<input type="text" ID="txtSecondNumber"><br>
Result:<br>
<input type="text" ID="txtResult"><br>
<br>
<input type="button" value='add' id='btnAdd' onclick="addTwoNumbers()" />
</form>
</body>
</html>
[CodePen代碼一起玩的(http://codepen.io/anthonyastige/pen/VjPOeR) –