How to pass form field value to java function on submit of form?

Question

Here is my form:

    <form  id="aform">
    <input type="text" id="rollno" name="rollno">
    <input type="button" value="show result" onclick="showResultFunction ('someurl.com','divtodisplayresult');>
    </form>

Question: Can I pass rollno entered in the function onclick as parameter? Like:

    onclick="showResultFunction ('someurl.com','divtodisplayresult',rollno);

Answer 1

试着做：

onclick="showResultFunction ('someurl.com','divtodisplayresult', document.getElementById('rollno').value);

Answer 2

Alternatively, in the Javascript function itself, you can access the rollno value in code:

function showResultFunction(url, div)
{
    var rollno = document.getElementById("rollno");
    alert(rollno.value);
}