问题
I have button in html
<input type="button" value="Clear">
<textarea id='output' rows=20 cols=90></textarea>
If I have an external javascript (.js) function, what should I write?
回答1:
Change in your html with adding the function on the button click
<input type="button" value="Clear" onclick="javascript:eraseText();">
<textarea id='output' rows=20 cols=90></textarea>
Try this in your js file:
function eraseText() {
document.getElementById("output").value = "";
}
回答2:
You need to attach a click
event handler and clear the contents of the textarea from that handler.
HTML
<input type="button" value="Clear" id="clear">
<textarea id='output' rows=20 cols=90></textarea>
JS
var input = document.querySelector('#clear');
var textarea = document.querySelector('#output');
input.addEventListener('click', function () {
textarea.value = '';
}, false);
and here's the working demo.
回答3:
<input type="button" value="Clear" onclick="javascript: functionName();" >
you just need to set the onclick event, call your desired function on this onclick event.
function functionName()
{
$("#output").val("");
}
Above function will set the value of text area to empty string.
回答4:
Your Html
<input type="button" value="Clear" onclick="clearContent()">
<textarea id='output' rows=20 cols=90></textarea>
Your Javascript
function clearContent()
{
document.getElementById("output").value='';
}
回答5:
You can simply use the ID attribute to the form and attach the <textarea>
tag to the form like this:
<form name="commentform" action="#" method="post" target="_blank" id="1321">
<textarea name="forcom" cols="40" rows="5" form="1321" maxlength="188">
Enter your comment here...
</textarea>
<input type="submit" value="OK">
<input type="reset" value="Clear">
</form>
来源:https://stackoverflow.com/questions/15968911/how-to-clear-text-area-with-a-button-in-html-using-javascript