C# 用面向对象的思想去编程
再接上一篇博文，之前写的两篇博文虽然实现了功能，但是和控件之间的粘性太大，依赖于控件进行操作，所以这篇博文主要用面向对象的思想做一个Demo，将逻辑层与显示层剥离开
首先新建一个窗体文件，搭建界面完毕：
新建一个类，命名为LawHelper
在LawHelper里新建两个对象，分别存放法律法规的名称编号和具体的位置：
public class Law { public string Nmae; public int ID; } public class LawNode { public string Name; public int Level; public int Parent; public int ID; public string LawName; public int LawID; }
再新建三个函数，分别对应着界面上的combobox选项，左边树状图的Node的具体位置以及右边textbox里的具体法律条款的显示：
public List<Law> GetLaws() { //实例化Law类 Law law = new Law(); return null; } public List<LawNode> GetLawNodes(Law law) { LawNode lawNode = new LawNode(); return null; } public string GetLawText(LawNode lawnode) { return null; }
编写第一个函数GetLaws()，获取到对应的法律法规的名称：
public List<Law> GetLaws() { //新建List List<Law> laws = new List<Law>(); //输入想关联的数据库的基本信息 SqlConnection conn = new SqlConnection(@"server = DESKTOP-5SDB4D4;Initial Catalog= test;User ID=sa;Password=lmz123LMZ"); //打开数据库连接 conn.Open(); //sql语句 string str = " select * from [test].[dbo].[TRaw] where c1 = 0"; //创建命令对象 SqlCommand lo_cmd = conn.CreateCommand(); lo_cmd.CommandText = str; SqlDataReader dtr = lo_cmd.ExecuteReader(); while (dtr.Read()) { //实例化Law类 Law law = new Law(); //法律名称 law.Nmae = (string)dtr["c3"]; //法律代码 law.ID = (int)dtr["c0"]; //将值赋到List中 laws.Add(law); } return laws; }
值得一提的是，我一开始将对象的实例放在了循环的外面，导致往List赋值的时候后面的值会将前面的值全部覆盖，解决方法就是在循环里实例化
编写第二个和第三个函数，分别获取具体的法律条文的位置以及输出最后的法律条文信息
编写完成后去主界面编写程序，首先实例化LawHelper类：
//实例化LawHelper类 LawHelper lawhelper = new LawHelper(); Law law = new Law(); List<LawNode> lawslocation = new List<LawNode>();
再对应编写对应的函数代码，具体代码如下显示：
LawHelper：
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Data.SqlClient; namespace WindowsFormsApp4 { public class Law { public string Name; public int ID; } public class LawNode { //节点的名称 public string name; //法律的层级 public int Level; //父节点 public int Parent; //具体法律条例的ID public int ID; //所选法律名称对应的编号 public int LawID; } public class LawHelper { //获取带法律名称及对应的法律编号 public List<Law> GetLaws() { //新建List List<Law> laws = new List<Law>(); //输入想关联的数据库的基本信息 SqlConnection conn = new SqlConnection(@"server = DESKTOP-5SDB4D4;Initial Catalog= test;User ID=sa;Password=lmz123LMZ"); //打开数据库连接 conn.Open(); //sql语句 string str = " select * from [test].[dbo].[TRaw] where c1 = 0"; //创建命令对象 SqlCommand lo_cmd = conn.CreateCommand(); lo_cmd.CommandText = str; SqlDataReader dtr = lo_cmd.ExecuteReader(); while (dtr.Read()) { //实例化Law类 Law law = new Law(); //法律名称 law.Name = (string)dtr["c3"]; //法律代码 law.ID = (int)dtr["c0"]; //将值赋到List中 laws.Add(law); } dtr.Close(); conn.Close(); return laws; } //获取法律条文的位置 public List<LawNode> GetLawNodes(Law law) { //新建List存放对应的值 List<LawNode> lawslocation = new List<LawNode>(); SqlConnection conn = new SqlConnection(@"server = DESKTOP-5SDB4D4;Initial Catalog= test;User ID=sa;Password=lmz123LMZ"); //打开数据库连接 conn.Open(); //sql语句 string str = " select * from [test].[dbo].[TRaw] where c0 =" + law.ID; //创建命令对象 SqlCommand lo_cmd = conn.CreateCommand(); lo_cmd.CommandText = str; SqlDataReader dtr = lo_cmd.ExecuteReader(); while (dtr.Read()) { //实例化LawNode类 LawNode lawNode = new LawNode(); //层级 lawNode.Level = (int)dtr["c4"]; //法律名称代码 lawNode.LawID = (int)dtr["c0"]; //父节点 lawNode.Parent = (int)dtr["c1"]; //法律名称代码 lawNode.ID = (int)dtr["c2"]; //将值赋到List中 lawslocation.Add(lawNode); } dtr.Close(); conn.Close(); return lawslocation; } //获取具体的法律条文 public string GetLawText(LawNode lawnode) { //获取到法律的层级 int level = lawnode.Level; //获取到法律的编号 int ID = lawnode.ID; //获取法律名称的ID int LawID = lawnode.LawID; string lawItem = ""; SqlConnection conn = new SqlConnection(@"server = DESKTOP-5SDB4D4;Initial Catalog= test;User ID=sa;Password=lmz123LMZ"); //打开数据库连接 conn.Open(); //sql语句 string str = "select * from [test].[dbo].[TRaw] where c4 =" + level + "and c0 = " + LawID + "and c2 = " + ID; //创建命令对象 SqlCommand lo_cmd = conn.CreateCommand(); lo_cmd.CommandText = str; SqlDataReader dtr = lo_cmd.ExecuteReader(); while (dtr.Read()) { if((int)dtr["c6"] == 1) { //获取到具体的法律条例 lawItem = (string)dtr["c3"]; } } dtr.Close(); conn.Close(); return lawItem; } } }
Form1：
using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; namespace WindowsFormsApp4 { public partial class Form1 : Form { //实例化LawHelper类 LawHelper lawhelper = new LawHelper(); Law law = new Law(); List<LawNode> lawslocation = new List<LawNode>(); public Form1() { InitializeComponent(); SetComboboxValue(); comboBox1.SelectedIndex = 0; } //设置combobox1的值 public void SetComboboxValue() { List<Law> laws = lawhelper.GetLaws(); for (int i = 0;i< laws.Count; i++) { comboBox1.Items.AddRange(new object[] { laws[i].Name}); } } //选择不同的法律法规 private void comboBox1_SelectedValueChanged(object sender, EventArgs e) { //获取到选中的法律名称 int inx = comboBox1.SelectedIndex; //树节点清空 treeView1.Nodes.Clear(); List<Law> laws = lawhelper.GetLaws(); law.Name = laws[inx].Name; law.ID = laws[inx].ID; lawslocation = lawhelper.GetLawNodes(law); int count = 1; //循环所有的节点 for (int i = 0; i < lawslocation.Count; i++) { //当level层级为1时，生成所有的父节点 if (lawslocation[i].Level == 1) { TreeNode node = new TreeNode(); node.Text = "第" + NumberToChinese(count) + "条"; treeView1.Nodes.Add(node); count++; lawslocation[i].name = node.Text; } //当父节点ID与法律法规ID相吻合的时候，生成子节点 //if () //{ //} } } //单击节点弹出消息 private void treeView1_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e) { TreeNode TN = e.Node; int inx = comboBox1.SelectedIndex; List<Law> laws = lawhelper.GetLaws(); law.Name = laws[inx].Name; law.ID = laws[inx].ID; // List<LawNode> lawslocation = lawhelper.GetLawNodes(law); for (int i = 0; i < lawslocation.Count; i++) { LawNode getinfo = new LawNode(); if (TN.Text == lawslocation[i].name) { getinfo.ID = lawslocation[i].ID; getinfo.LawID = lawslocation[i].LawID; getinfo.Level = lawslocation[i].Level; textBox1.Text = lawhelper.GetLawText(getinfo); break; } } } //数字转中文 public string NumberToChinese(int number) { string res; string str = number.ToString(); string schar = str.Substring(0, 1); switch (schar) { case "1": res = "一"; break; case "2": res = "二"; break; case "3": res = "三"; break; case "4": res = "四"; break; case "5": res = "五"; break; case "6": res = "六"; break; case "7": res = "七"; break; case "8": res = "八"; break; case "9": res = "九"; break; default: res = "零"; break; } if (str.Length > 1) { switch (str.Length) { case 2: case 6: res += "十"; break; case 3: case 7: res += "百"; break; case 4: res += "千"; break; case 5: res += "万"; break; default: res += ""; break; } res += NumberToChinese(int.Parse(str.Substring(1, str.Length - 1))); } res = res.Replace("十零", "十").Replace("一十", "十"); return res; } } }
最后的效果如图所示：
