填充后 ListView 空白

Question

我有一个Dictionary<string, string>对象，它的数据应该通过在TextBox控件中提交的文本进行实时过滤，然后在ListView控件中显示。

我想出的解决方案是：

• 转换Dictionary<string, string>为DataTable

• 使用文本框的TextChanged事件触发过滤器

• 将过滤后的记录放入DataRow[]数组，将所述数组作为参数传递给自定义方法以填充ListView对象

现在，这就是我转换字典的方式：

static DataTable dtDepartments { get; set; }

static Dictionary<string, string> GetDepartments(string _depNum, out bool _isOff) 

 {

     // retrieve the list from a SQL Server DB

 }

public myForm()

{

    InitializeComponent();

    Dictionary<string, string> Departments = new Dictionary<string, string>();

    Departments = GetDepartments(string.Empty, out bool _isOff);

    dtDepartments = new DataTable();

    dtDepartments.TableName = "DEPARTMENTS";

    DataColumn idColumn = dtDepartments.Columns.Add("NUM", typeof(string));

    dtDepartments.Columns.Add("NAME", typeof(string));

    dtDepartments.PrimaryKey = new DataColumn[] { idColumn };

    foreach(KeyValuePair<string,string> kvP in Departments)

    {

        dtDepartments.Rows.Add(new object[] { kvP.Key, kvP.Value });

    }

}

这就是我在事件方法中填充列表的方式

private void txtFilter_TextChanged(object sender, EventArgs e)

{

    string filter = "NAME LIKE '%" + txtFilter.Text + "%'";

    DataRow[] foundRows = dtDepartments.Select(filter);

    if (foundRows.Length > 0)

    {

        lvDepartments.Visible = true;

        ResizeListView(foundRows.Length);

        PopulateListView(foundRows);

    }

}

void ResizeListView(int _rows)

{

    lvDepartments.Height = Math.Min(25 + (20 * _rows), 205);

}

void PopulateListView(DataRow[] _foundRows)

{

    lvDepartments.Items.Clear();

    ListViewItem depNum = new ListViewItem("NUM", 0);

    ListViewItem depName = new ListViewItem("NAME", 0);

    foreach (DataRow row in _foundRows)

    {

        depNum.SubItems.Add(row.Field<string>("NUM"));

        depName.SubItems.Add(row.Field<string>("NAME"));

    }

该DataRow[]阵列被正确填充，ResizeListView(int _rows)方法做它的适应名单高度作业时，ListView正确显示的列标题，但剩下的只是空行。