/// <summary>
/// 将分类类别转换为TreeNodes
/// </summary>
/// <param name="categoryService">扩展类：CategoryService</param>
/// <param name="categories">要转换成节点分类集合</param>
/// <param name="targetType">点击分类时打开新页还是在本页打开</param>
/// <param name="idPrefix">节点ID前缀</param>
/// <param name="checkedCategoryId">当前选中的CategoryId</param>
/// <param name="openLevel">默认打开的层级</param>
/// <returns>TreeNodes列表</returns>
public static IList<TreeNode> CategoriesToTreeNodes(this CategoryService<Category> categoryService, IList<Category> categories, TargetType targetType, string idPrefix, long? checkedCategoryId, int? openLevel)
{
//本方法将分类转换成TreeNodes，其中，哪些节点展开还是闭合的逻辑较为复杂，如下：
//关于哪些节点展开哪些节点闭合，逻辑实现如下：
//1 首先，若checkedCategoryId有值，则这个分类的所有父级分类展开，其他分类全部折叠；
//2 其次，若checkedCategoryId无值，openLevel有着，则深度小于等于openLevel的分类展开，其他分类折叠；
//3 若若checkedCategoryId和openLevel都没有值，则所有分类折叠。
IList<TreeNode> nodes = new List<TreeNode>();
if (categories != null && categories.Count > 0)
{
//若当前有选中的分类，则获取其所有的父级分类Id集合
List<long> checkedCategoryIds = new List<long>();
if (checkedCategoryId.HasValue && checkedCategoryId.Value > 0)
GetParentCategoryIDs(categoryService, checkedCategoryId.Value, checkedCategoryIds);
//通过Category组装TreeNode
foreach (Category category in categories)
{
TreeNode node = new TreeNode();
node.Id = idPrefix + category.CategoryId.ToString();
node.IsChecked = (checkedCategoryId == category.CategoryId);
node.IsOpened = IsOpenedNode(category, checkedCategoryIds, openLevel);
node.IsParent = category.ChildCount > 0;
node.Name = category.CategoryName;
node.ParentId = idPrefix + category.ParentId.ToString();
node.Target = targetType;
node.Url = string.Empty;
nodes.Add(node);
}
}
return nodes;
}
/// <summary>
/// 用户创建新实体时使用
/// </summary>
/// <returns></returns>
public static TreeNode New()
{
TreeNode treenode = new TreeNode()
{
Target = null,
IconName = string.Empty,
Url = string.Empty
};
return treenode;
}