Question

我有一个连接到SQL Server数据库的简单应用程序，我试图从服务器提取数据以将其添加到WPF ListView。我已经完成了我认为很难的部分，并成功地提取了数据 - 已经证实了这一点。但是当我尝试将其添加到我现有的列表视图时，列表视图仍然是空白的。这是我要添加的代码。

GetEmployees使用中间层类连接到数据库并检索Employee的属性。它成功创建了所有这些变量，并从数据库中分配它们的值。底线 - lvwEmpSearch.Items.Add(emp);是不起作用的。

编辑：代码已调整。

添加到列表视图的代码：

public ObservableCollection<EmployeeViewModel> Employees { get; set; } = new ObservableCollection<EmployeeViewModel>();

private void btnFindAllEmployees_Click(object sender, RoutedEventArgs e)
    {

        List<Employee> empList = GetEmployees();
        foreach (Employee emp in empList)
        {
            var model = new EmployeeViewModel
            {
                empID = emp._empID,
                Name = emp._fName + " " + emp._lName,
                Address = emp._address + ", " + emp._city + ", " + emp._state + " " + emp._zip,
                HireDate = emp._doH,
                Phone = emp._phone,
                PayRate = emp._payRate,
                Email = emp._email,
            };
            Employees.Add(model);
        }
    }

EmployeeViewModel类：

public class EmployeeViewModel
{
    public int empID { get; set; }
    public string Name { get; set; }
    public string Address { get; set; }
    public DateTime HireDate { get; set; }
    public string Phone { get; set; }
    public decimal PayRate { get; set; }
    public string Email { get; set; }

}

Answer 1

创建一个ViewModel来保存您想要显示的项目信息。

基于列绑定，您正在寻找类似

的内容

public class EmployeeViewModel {
    public int ID { get; set; }
    public string Name { get; set; }
    public string Address { get; set; }
    public DateTime HireDate { get; set; }
    public string Phone { get; set; }
    public decimal PayRate { get; set; }
    public string Email { get; set; }
}

创建一个可观察的集合来保存项目

public ObservableCollection<EmployeeViewModel> Employees { get; set; } = new ObservableCollection<EmployeeViewModel>();

并允许视图绑定到列表

<ListView  x:Name="lvwEmpSearch"  ItemsSource="{Binding Employees}" >
    <!-- ...removed for brevity -->
</ListView>

现在所需要的只是在主ViewModel中填充集合

List<Employee> empList = GetEmployees();
foreach (Employee emp in empList) {
    var model = new EmployeeViewModel {
        ID = emp._empID,
        Name = emp._fName + " " + emp._lName,
        Address = emp._address + ", " + emp._city + ", " + emp._state + " " + emp._zip,
        HireDate = emp._doH,
        Phone = emp._phone,
        PayRate = emp._payRate,
        Email = emp._email,
    };
    Employees.Add(model);
}

您似乎正在执行代码中的所有操作，因此您需要绑定视图。最初的假设是您遵循MVVM模式。

//CTOR
public EmployeesView() {
    this.InitializeComponents();
    this.Employees = new ObservableCollection<EmployeeViewModel>();
    //Bind the view so that 
    this.DataContext = this;
}

public ObservableCollection<EmployeeViewModel> Employees { get; private set; }

private void btnFindAllEmployees_Click(object sender, RoutedEventArgs e) {
    //...code removed for brevity
}

Answer 2

尝试执行以下操作：

在您看来：

{{ newNewsForm?.value?.content.replace('\n','<br/>') }}

在视图后面的代码中：

<ListView ItemsSource="{Binding Employees}">
      <ListView.View>
        <GridView>
          <GridViewColumn Header="ID" DisplayMemberBinding="{Binding ID}"></GridViewColumn>
          <GridViewColumn Header="Name" DisplayMemberBinding="{Binding Name}"></GridViewColumn>
        </GridView>
      </ListView.View>
    </ListView>

MainViewModel代码：

 public MainWindow() {
  InitializeComponent();

  DataContext = new MainViewModel();
}

Answer 3

你应该能够创建一个包含你的员工的ObservableCollection并将它们绑定到ItemsSource。

private ObservableCollection<Employee> _employees = new ObservableCollection<Employee>();
public ObservableCollection<Employee> Employees
{
    get { return _employees; }
    protected set
    {
        if (_employees == value)
            return;
        _employees = value;
        OnPropertyChanged("Employees");
    }
}

然后像这样绑定它：

<ListView ItemsSource="{Binding Employees}"/>

在代码中你可以填写：

Employees.AddRange(GetEmployees());

无法将项目添加到WPF ListView

3 个答案: