CSharp动态添加Combox项的几种方法

Posted 2020-11-27 sures

 1 namespace AAFormsApp1
 2 {
 3     public partial class Form1 : Form
 4     {
 5         public Form1()
 6         {
 7             InitializeComponent();
 8         }
 9 
10         private void button1_Click(object sender, EventArgs e)
11         {
12             DataTable dt = new DataTable();
13             dt.Columns.Add("Display");
14             dt.Columns.Add("Value");
15             for (int i = 0; i < 5; i++)
16             {
17                 DataRow dr = dt.NewRow();
18                 dr["Display"] = "显示" + i.ToString();
19                 dr["Value"] = i;
20                 dt.Rows.Add(dr);
21             }
22             comboBox1.DataSource = dt;
23             comboBox1.DisplayMember = "Display";
24             comboBox1.ValueMember = "Value";
25         }
26 
27         private void button2_Click(object sender, EventArgs e)
28         {
29             List<KeyValuePair<int, string>> cbList = new List<KeyValuePair<int, string>>();
30             Dictionary<int, string> dic = new Dictionary<int, string>();
31             cbList.Add(new KeyValuePair<int, string>(1, "my"));
32             cbList.Add(new KeyValuePair<int, string>(2, "is"));
33             cbList.Add(new KeyValuePair<int, string>(3, "hero"));
34 
35             for (int i = 0; i < 5; i++)
36             {
37                 dic.Add(i, i.ToString());
38             }
39             comboBox1.DataSource = cbList;
40             //comboBox1.DataSource = dic; //不能是字典，这里添加会失败
41             comboBox1.DisplayMember = "Value";
42             comboBox1.ValueMember = "Key";
43         }
44 
45         private void button3_Click(object sender, EventArgs e)
46         {
47             string[] daysOfWeek =  { "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday" };
48             comboBox1.DataSource = daysOfWeek;
49         }
50 
51         private void button4_Click(object sender, EventArgs e)
52         {
53             //如果要一个一个的添加，前面不能指定DataSource，否则失败
54             string[] daysOfWeek = { "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday" };
55             foreach (var d in daysOfWeek)
56             {
57                 comboBox1.Items.Add(d);
58             }
59             //或者//comboBox1.Items.AddRange(daysOfWeek);
60         }
61 
62         private void button5_Click(object sender, EventArgs e)
63         {
64             //如果要一个一个的添加，前面不能指定DataSource，否则失败
65             comboBox1.Items.Insert(0, new ComboBoxItem("0", "请选择"));
66             comboBox1.Items.Insert(1, new ComboBoxItem("1", "根目录"));
67         }
68     }
69 
70     internal class ComboBoxItem : Object
71     {
72         private string _value;
73         private string _text;
74         public ComboBoxItem(string v, string t)
75         {
76             _value = v;
77             _text = t;
78         }
79         public string Text
80         {
81             get { return _text; }
82         }
83         public string Value
84         {
85             get { return _value; }
86         }
87         public override string ToString()
88         {
89             return _text;
90         }
91 
92     }
93 }