赋值后TextBlock未即时更新问题求助（WPF DataGrid场景）

核心问题是你的itemAsm类没有实现INotifyPropertyChanged接口，WPF的数据绑定依赖这个接口的PropertyChanged事件来通知UI更新属性值变化。直接修改Selected.destLocCol时，UI无法感知属性变更，只有双击触发UI重新绑定（比如进入编辑模式再退出）才会显示新值。

具体修改步骤 #

1. 让itemAsm类实现INotifyPropertyChanged接口 #

修改itemAsm类，添加接口实现与属性变更通知逻辑：

using System.ComponentModel;
using System.Runtime.CompilerServices;

public class itemAsm : INotifyPropertyChanged
{
    private string _prefCol;
    private string _fileLocCol;
    private string _suffCol;
    private string _destLocCol;

    public string prefCol
    {
        get => _prefCol;
        set
        {
            _prefCol = value;
            OnPropertyChanged();
        }
    }

    public string fileLocCol
    {
        get => _fileLocCol;
        set
        {
            _fileLocCol = value;
            OnPropertyChanged();
        }
    }

    public string suffCol
    {
        get => _suffCol;
        set
        {
            _suffCol = value;
            OnPropertyChanged();
        }
    }

    public string destLocCol
    {
        get => _destLocCol;
        set
        {
            _destLocCol = value;
            OnPropertyChanged();
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;

    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

2. 额外优化建议 #

如果后续需要通过代码修改Selected属性来更新UI，窗口类也需要实现INotifyPropertyChanged接口，并给Selected添加变更通知：

using System.ComponentModel;
using System.Runtime.CompilerServices;

public partial class unitCopierFrm : Window, INotifyPropertyChanged
{
    private itemAsm _selected;
    public itemAsm Selected
    {
        get => _selected;
        set
        {
            _selected = value;
            OnPropertyChanged();
        }
    }

    public ObservableCollection<itemAsm> SelectedAsm { get; set; }

    public unitCopierFrm()
    {
        InitializeComponent();
        SelectedAsm = new ObservableCollection<itemAsm>();
        DataContext = this;
    }

    // 省略原有按钮点击事件代码...

    public event PropertyChangedEventHandler PropertyChanged;
    protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }
}

内容的提问来源于stack exchange，提问作者ZeroPanda