This paper introduces a more general method to get the checkbox value, which is helpful to the novice.
Copy Code code as follows:
<script type= "Text/javascript" >
Note: Use Javascript to validate the values of multiple-selection boxes (checkboxes) in forms (form)
Author: codebit
function Getcheckboxvalue (checkbox)
{
if (!checkbox.length && checkbox.type.toLowerCase () = = ' checkbox ')
{return (checkbox.checked)? Checkbox.value: ';}
if (checkbox[0].tagname.tolowercase ()!= ' Input ' | |
Checkbox[0].type.tolowercase ()!= ' checkbox ')
{return ';}
var val = [];
var len = checkbox.length;
for (i=0; i<len; i++)
{
if (checkbox[i].checked)
{
Val[val.length] = Checkbox[i].value;
}
}
Return (Val.length) Val: ';
}
</script>
Like radio, it is the same name, there are multiple values, we can't follow the normal text box when we get the checkbox value. value, but to determine which is selected.
When a set of checkbox has more than one option, we can determine whether an option is selected to return a value by looping, Checkbox[i], but when a set of CheckBox has only one option, the way to get the value changes, in the code ( checkbox.checked)? Checkbox.value: '; Directly to determine if it is selected, and then return the corresponding value.
The code passed in above is a CheckBox object, such as:
Copy Code code as follows:
var checkboxtest = document.forms[' testform '].elements[' checkboxtest '];
if (Getcheckboxvalue (checkboxtest) = = ")
{ ...... }
Perform the actions you want based on the results of your judgment.
