简单的getElementbyId无法在Safari中运行，但Chrome可以运行

Question

我在下面有以下AJAX请求，可以在chrome中使用但不是safari吗？我认为Chrome使用的是Safari HTML。我的Javascript控制台在safari和chrome上都没有错误。第一个submit（）函数检查重复的条目，如果没有重复的条目，则第二个ajax提交数据。一切都适用于Chrome，但不适用于Safari。有什么建议吗？

    function submit() {
        var bin = document.getElementById("bin_number").value;
        var barcode = document.getElementById("barcode").value;
        document.getElementById("alert").className = '';
        document.getElementById("alert").innerHTML = '';
        $.ajax({
            url: '?a=ajax_check_scan_to_bin&bin='+bin+'&barcode='+barcode+'',
            type: 'GET',
            contentType: "text/xml",
            dataType: "text",
            success: function(data){
                if(data > 0) {
                    document.getElementById("form-group-"+id).className = 'form-group has-error  has-feedback';
                    document.getElementById("alert").className = 'alert alert-danger';
                    document.getElementById("alert").innerHTML = 'This Barcode and Bin have Been Scanned Already';

                } else {
                    document.getElementById("submit-btn").className = 'btn btn-block btn-lg btn-success';
                    submit_form();    
                }
            },
            error: function(){
                alert('some error happened');
            }
        }); 
    }      

function submit_form(){
            var bin = document.getElementById("bin_number").value;
            var barcode = document.getElementById("barcode").value;
                             $.ajax({
                            url: '?a=post_scantobin&bin_number='+bin+'&barcode='+barcode+'',
                            type: 'GET',
                            contentType: "text",
                            dataType: "text",
                            success: function(data){
                                if(data == '0') {
                                        document.getElementById("alert").className = 'alert alert-warning';
                                        document.getElementById("alert").innerHTML = 'Transaction Entered - Unable to Load into External Database';
                                } else if (data == '1') {
                                    document.getElementById("alert").className = 'alert alert-success';
                                    document.getElementById("alert").innerHTML = 'Transaction Entered Successfully';
                                } else {
                                    document.getElementById("alert").className = 'alert alert-danger';
                                    document.getElementById("alert").innerHTML = data;
                                }
                            },
                            error: function(){
                                alert('some error happened');
                            }
                        });    
        }
    </script>

    <div class="panel panel-default">
      <div class="panel-body">
    <div class="row clearfix">
            <div class="col-md-4 col-md-offset-4 column">
                <div class="" id='alert' role="alert"></div>
                    <div class="form-group" id="form-group-bin">
                         <label for="bin_number" class='control-label'>Scanning to Bin</label><input onchange="check('bin');" type="number" class="form-control input-lg" name="bin_number" id="bin_number" />
                    </div>
                    <div class="form-group" id='form-group-barcode'>
                         <label for="barcode" class='control-label'>Item Barcode:</label><input onchange="check('barcode');" type="text" class="form-control input-lg" name="barcode" id="barcode" />
                    </div>
                    <button id="submit-btn" type="button" onblur="submit();" class="btn btn-block btn-lg btn-default">Submit</button>
            </div>
        </div>
        </div>
    </div>