Clarification on binding Listbox.SelectedItem in MVVM

问题

I have a ListBox in one of my user controls in which I would like to get the SelectedItem, to be used in the ViewModel. The ListBox is composed of TextBlocks.

This question is pretty much a straight up answer to my question, but I don't understand where DisneyCharacter (his collection type) comes from, or how it relates to the ListBox.

Would mine be of type TextBlock?

XAML for ListBox as requested:

<ListBox Margin="14,7,13,43" Name="commandListBox" Height="470" MinHeight="470" MaxHeight="470" Width="248" >
               <TextBlock Text="Set Output" Height="Auto" Width="Auto" />
               <TextBlock Text="Clear Output" Height="Auto" Width="Auto" />
               <TextBlock Text="Follow Left Tape Edge" Height="Auto" Width="Auto" />
               <TextBlock Text="Follow Right Tape Edge" Height="Auto" Width="Auto" />
               <TextBlock Text="Follow Tape Center" Height="Auto" Width="Auto" /></ListBox>

回答1:

Since the output from a TextBlock is a string, you would bind to a string property, you would bind to a string in your ViewModel or code behind.

<ListBox SelectedItem = "{Binding myString}">
     .......
</ListBox>

Then in whatever your datacontext is set up a string Property like this

public string myString {get; set;}

Now whenever you click on an item, the text from that textblock will be in the myString variable.

if you were using MVVM model your property would look like this:

 private string _myString;

    /// <summary>
    /// Sets and gets the myString property.
    /// Changes to that property's value raise the PropertyChanged event. 
    /// </summary>
    public string myString
    {
        get
        {
            return _myString;
        }

        set
        {
            if (_myString == value)
            {
                return;
            }

            RaisePropertyChanging("myString");
            _myString = value;
            RaisePropertyChanged("myString");
        }
    }

Let me know if you have any questions.

来源：https://stackoverflow.com/questions/19123215/clarification-on-binding-listbox-selecteditem-in-mvvm

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mvvm

listbox