Java Script Function To Return Selected Checkbox Value

Get the selected checkbox value from the group of checkbox list in Javascript. I wrote one function to return the selected checkbox value in Javascript.

<script type='text/javascript>

// Java Script function to return the selected checkbox value
function Checkbox_Selection_Value_From_Group (){
	fileid= $(\"input[name='filegroup[]']:checked\").map(function() { 
            return this.value; 
          }).get();
    if(fileid==''){
        alert('Select Minimum One Check Box');
        return false;
    }else{
	// You Will get comma separated value		
        // 1,2
       return 'id='+fileid;
    }
}
</script>

<input type="checkbox" id="filegroup" name="filegroup[]" value="1">
<input type="checkbox" id="filegroup" name="filegroup[]" value="2">
<input type="checkbox" id="filegroup" name="filegroup[]" value="3">
<input type="checkbox" id="filegroup" name="filegroup[]" value="4">