How to find out what character key is pressed in Javascript?

How to find out what character key is pressed in Javascript?

<div class="form-group col-md-6">
                                <label for="First_Name">First Name <span class="text-danger">*</span></label>
                                <input class="form-control" id="txt_First_Name" type="text" name="txt_First_Name" placeholder="Enter First Name" onkeypress="return searchKeyPressByName(event);" />
                            </div>

<div class="form-group col-md-12 text-center">
                                <button class="btn btn-primary" type="button" id="btn_searchByName" name="btn_searchByName">Search</button>
                            </div>
<script>
    function searchKeyPressByName(e) {
        e = e || window.event;        
        if (e.keyCode == 13) {  
             alert(e.keyCode)          
            document.getElementById('btn_searchByName').click();
            return false;
        }
        return true;
    }
</script>

2020-02-26