Krajee 引导程序文件上传插件仅接受图像文件类型

我正在尝试使用 krajee 引导文件上传来 excel（.xls） 文件上传，但它似乎只接受图像文件。

这是我的Javascript代码：

            $("#dosyalar").fileinput({
                    uploadUrl: "ajax/upload_files.php",
                    uploadAsync: true,
                    previewFileType:'any',
                    language:"tr",
                    uploadExtraData: function() {
                        return { donem: $('#donem').val() };
                    }
                }).on('filebatchuploaderror', function(event, data, previewId, index) {
                    var form = data.form,
                        files = data.files,
                        extra = data.extra,
                        response = data.response,
                        reader = data.reader;
                    console.log(response);
            }).on('filebatchuploadsuccess', function(event, data, previewId, index) {
                    var form = data.form,
                        files = data.files,
                        extra = data.extra,
                        response = data.response,
                        reader = data.reader;
                    alert (extra.bdInteli + " " +  response.uploaded);
                    console.log(response);
            });

这里是用于测试的PHP代码：

// upload.php
// 'images' refers to your file input name attribute
if (empty($_FILES['dosyalar'])) {
    echo json_encode(['error'=>'No files found for upload.']);
    // or you can throw an exception
    return; // terminate
}

每次尝试上传批处理 excel 文件时都显示No files found for upload.似乎不接受.xls扩展。

如何使用此插件上传 excel 文件？

谢谢