http://www.cnblogs.com/xxm/archive/2006/10/18/532009.html 写完一部分代码。都快要四点了。最近做项目,好久没有往博客上放东西了。趁着还有些精神,赶紧把上次没有发布的代码补上。使用TreeList都有两个月了。发现自己使用它的Tag属性达到了变态的地步,
http://www.cnblogs.com/xxm/archive/2006/10/18/532009.html
写完一部分代码。都快要四点了。最近做项目,好久没有往博客上放东西了。趁着还有些精神,赶紧把上次没有发布的代码补上。使用TreeList都有两个月了。发现自己使用它的Tag属性达到了变态的地步,在Tag属性里放的Struct里面的东西越来越多。在某种程度上。没有这个属性。我的好多工作是无法完成的。考虑到装箱和拆箱的过程,却也无可奈何。这是一个通过DataTable来自动绑定TreeList的类,考虑到了部分数据显示和部分字段显示,在每个SimpleBind的重载中都加入了这一部分的处理,强调一点。我所处理的数据都是以父子节点为基础的绑定。同时。子节点是以1开始。父节点是以
0开始。这样在存入父子节点ID的时候要注意。代码如下,谨供自己和自己一样的菜鸟参考。
1using System.Collections ;
2using System.Data ;
3using BusinessEntity;
4using PersistenceLayer;
5using DevExpress.XtraTreeList ;
6using DevExpress.XtraTreeList.Nodes ;
7using DevExpress.XtraTreeList.Columns ;
8namespace NskProject
9{
10 /**////
11 /// 一些实现或辅助绑定TreeList的静态方法。
12 ///
13 public class BindTreeList
14 {
15 /**////
16 /// 初级绑定方法,给定的表中有父子关系的字字段,默认情况下表内所有字段都被绑定到控件内
17 ///
18 /// 数据源表
19 /// 需要绑定的控件
20 public static void SimpleMode(DataTable Dt,TreeList Ti)
21 {
22 if(ParentFieldName==null && ChildFieldName==null)
23 {
24 return;
25 }
26
27 Ti.ParentFieldName=ParentFieldName;
28 Ti.KeyFieldName=ChildFieldName;
29 Ti.DataSource=Dt;
30 Ti.PopulateColumns();
31 return;
32 }
33 /**////
34 /// 初级绑定方法:在前一方法的基础上增加了将某一字段加入到Tag属性中去。保存附加信息
35 /// 该表在赋值前以父节点为基础进行了排序
36 ///
37 /// 数据源表
38 /// 附加到Tag属性中的字段
39 /// 需要绑定的控件
40 public static void SimpleMode(DataTable Dt,DataColumn TagColumn,TreeList Ti)
41 {
42 if(ParentFieldName==null && ChildFieldName==null)
43 {
44 return;
45 }
46 int TagColumnIndex=Dt.Columns.IndexOf(TagColumn);
47 foreach(DataRow dr in Dt.Rows)
48 {
49 object[] Data=new object[Dt.Columns.Count-3];
50 object Tag=new object() ;
51 Object[]Source=dr.ItemArray;
52 int count=0;
53 //显示数据与附加数据分离
54 for(int i=0;i
56 if(i!=TagColumnIndex &&i!=-1)
57 {
58 Data[count]=Source[count];
59 count++;
60 }
61 else
62 {
63 Tag=Source[i];
64 }
65 }
66 int ParentID=Convert.ToInt32(dr[ParentFieldName]);
67 int ChildID=Convert.ToInt32(dr[ChildFieldName]);
68 int Balance=0;
69 if(ParentID==0)
70 {
71 TreeListNode Node=Ti.AppendNode(Data,null);
72 Node.Tag=Tag;
73 if(Node.Id!=ChildID)
74 {
75 Balance=ChildID;
76 //可能存在只取一部分数据的情况,在这种情况下,取控件内ID与表内ID之间的差额
77 }
78 }
79 else
80 {
81 TreeListNode ParentNode;
82 if(Balance>0)//两种不同情况的取得父节点的方法
83 {
84 ParentNode=Ti.FindNodeByID(ParentID-Balance);
85 }
86 else
87 {
88 ParentNode=Ti.FindNodeByID(ParentID-1);
89 }
90 if(ParentNode!=null)
91 {
92 TreeListNode Node=Ti.AppendNode(Data,ParentNode);
93 Node.Tag=Tag;
94 }
95 }
96 }
97 }
98 /**////
99 /// 针对有时候并不是加载一张表内的所有内容,对此加以变形,对于存在于表中不在列表内的字段
100 /// 给删除,对于不在表内而在列表内的值赋空值加入列表内
101 ///
102 /// 数据源表
103 /// 需要在TreeList中显示的字段列表
104 /// 需要绑定的控件
105 public static void SimpleMode(DataTable Dt,string Fields,TreeList Ti)
106 {
107 Ti.Nodes.Clear();
108 int Balance=0;
109 string[] FieldList=Fields.Split(",".ToCharArray());
110 if(ParentFieldName==null && ChildFieldName==null)
111 {
112 return;
113 }
114 foreach(DataRow dr in Dt.Rows)
115 {
116 int index=0;
117 Object[] Data=new object[FieldList.Length];
118 foreach(string o in FieldList)
119 {
120 if(Dt.Columns.IndexOf(o)>-1)
121 {
122 string n=dr[o].ToString().Trim();
123 Data[index]=n;
124 }
125 else
126 {
127 Data[index]="";
128 }
129 index++;
130 }
131
132 int ParentID=Convert.ToInt32(dr[ParentFieldName]);
133 int ChildID=Convert.ToInt32(dr[ChildFieldName]);
134
135 if(ParentID==0)
136 {
137 TreeListNode Node=Ti.AppendNode(Data,null);
138 if(Node.Id!=ChildID-1)
139 {
140 Balance=Node.Id
142 }
143 }
144 else
145 {
146 TreeListNode ParentNode;
147 if(Balance>0)//两种不同情况的取得父节点的方法
148 {
149 ParentNode=Ti.FindNodeByID(ParentID-Balance);
150 }
151 else
152 {
153 ParentNode=Ti.FindNodeByID(ParentID-1);
154 }
155 if(ParentNode!=null)
156 {
157 TreeListNode Node=Ti.AppendNode(Data,ParentNode);
158
159 }
160 }
161 }
162 }
163 /**////
164 ///
165 ///
166 ///
167 ///
168 ///
169 ///
170 public static void SimpleMode(DataTable Dt,string Fields,TreeList Ti,string TagColumn)
171 {
172 Ti.Nodes.Clear();
173 int Balance=0;
174 string[] FieldList=Fields.Split(",".ToCharArray());
175 if(ParentFieldName==null && ChildFieldName==null)
176 {
177 return;
178 }
179 foreach(DataRow dr in Dt.Rows)
180 {
181 int index=0;
182 Object[] Data=new object[FieldList.Length];
183 foreach(string o in FieldList)
184 {
185 if(o!=TagColumn && Dt.Columns.IndexOf(o)>-1)
186 {
187 string n=dr[o].ToString().Trim();
188 Data[index]=n;
189 }
190 else
191 {
192 Data[index]="";
193 }
194 index++;
195 }
196
197 int ParentID=Convert.ToInt32(dr[ParentFieldName]);
198 int ChildID=Convert.ToInt32(dr[ChildFieldName]);
199
200 if(ParentID==0)
201 {
202 TreeListNode Node=Ti.AppendNode(Data,null);
203 Node.Tag =dr[TagColumn];
204 if(Node.Id!=ChildID)
205 {
206 Balance=ChildID;
207 //可能存在只取一部分数据的情况,在这种情况下,取控件内ID与表内ID之间的差额
208 }
209 }
210 else
211 {
212 TreeListNode ParentNode;
213 if(Balance>0)//两种不同情况的取得父节点的方法
214 {
215 ParentNode=Ti.FindNodeByID(ParentID-Balance);
216 }
217 else
218 {
219 ParentNode=Ti.FindNodeByID(ParentID-1);
220 }
221 if(ParentNode!=null)
222 {
223 TreeListNode Node=Ti.AppendNode(Data,ParentNode);
224 Node.Tag =dr[TagColumn];
225
226 }
227 }
228 }
229 }
230 private static string _ParentFieldName="";
231 private static string _ChildFieldName="";
232 public static string ParentFieldName
233 {
234 get{return _ParentFieldName;}
235 set{_ParentFieldName=value;}
236 }
237
238 public static string ChildFieldName
239 {
240 get{return _ChildFieldName;}
241 set{_ChildFieldName=value;}
242 }
243
244 }
245}
246
这是一个静态方法,在执行SimpleBind方法前。必须对ChildFieldName和ParentFieldName进行赋值,它们对应着Dt中的父子节点的列名。

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