问题
My HTML script is
<html>
<body>
<b><font color="green">Please select a check box to change the color of text </font> </b><br>
<input type="checkbox" name="red" id="chkbx" > Red<br>
<input type="checkbox" name="green" id="chkbx" value="1"> Green <br>
<input type="checkbox" name="blue" id="chkbx" value="2"> Blue <br>
<input type="checkbox" name="orange" id="chkbx" value="3"> Orange <br>
<input type="checkbox" name="yellow" id="chkbx" value="4"> Yellow <br>
<p id="demo"></p>
<button onclick="myfunction()">My Choice</button>
<br><br>
<h style="color: red; font-weight: bold;"> </h>
<p id="demo"></p>
i need to get the checkbox value in javascript and if any one checkbox is selected that colour will apply to a text to display on the output. how to do?
回答1:
First off - don't use the tag as it has been deprecated since 1999 use
<p style='font-weight:bold; color:green'>....</p>
Instead of checkboxs use radio buttons
<input type="radio" name="red" value="red" onClick="myFunction(this.value);"> Red<br>
Repeat the above for all possible selections.
Change your function myFunction() to myFunction( value ) and work from there. The information is passed directly to the function so there is no need to go looking for it.
来源：https://stackoverflow.com/questions/21668843/how-to-get-checkbox-value-in-javascript