Javascript Javascript将小写字母转换为大写字母
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Javascript to convert lowercase to upper case
提问by station
What is wrong with the following htmla and javascript code
以下htmla和javascript代码有什么问题
formToConvert.html
表单转换.html
<html>
<head>
<title>ExampleToConvert</title>
<script type = "text/javascript" src = "con.js"></script>
</head>
<body>
<form id ="myform">
<input type = "text" id = "field1" value = "Enter text Here"/><br/>
<input type ="submit" value = "submit" onclick = "convert()"/>
</form>
</body>
</html>
con.js
con.js
function convert()
{
var str ;
str = document.getElementById("field1");
document.writeln(str.toUpperCase());
}
Why is the above code not giving me the desired result?
为什么上面的代码没有给我想要的结果？
回答by James Johnson
You need to change it to this:
你需要把它改成这样：
var str = document.getElementById("field1").value;
document.writeIn(str.toUpperCase());
回答by GNi33
Try:
尝试：
str = document.getElementById("field1").value;
This is because getElementById returns a reference to your HTML Element, not the "text"-value that is contained.
这是因为 getElementById 返回对 HTML 元素的引用，而不是包含的“文本”值。
回答by Rion Williams
The following change should fix your issue:
以下更改应该可以解决您的问题：
str = document.getElementById("field1");
should be
应该
str = document.getElementById("field1").value;
