C# (UWP) - Access object dynamically from string-variable

Question

So I've written some code that creates TextBlocks from a list of strings by calling a for loop:

List<string> menuPages = new List<string>() { "Home", "Media", "Settings" };
//method called from constructor:
private void createHeaders ()
{
    for (int i=0; i<menuPages.Count; i++)
    {
        TextBlock iheader = new TextBlock();
        iheader.Name = menuPages[i];
        iheader.Text = menuPages[i];
        if (i==pageIndex)
        { iheader.FontSize = 36; }
        else
        { iheader.FontSize = 32; }
        stacky.Children.Add(iheader); //Adding button to stack panel
    }
}

Now I've been writing another method that would cycle through each TextBlock in a loop and change the text to whatever I intend. I'd gotten a foreach loop working for the stackPanel children: (TextBlock tBlock in stacky.Children) but I need to work with an indexed for loop. The code below is how I WANT to achieve this:

//Re-render headers
for (int i = 0; i < menuPages.Count; i++)
{
    //TextBlock menuPages[i].text = "foo";
}

Now of course the syntax above doesn't work so my question is, how can I address the TextBlocks from the strings in a list?

Martin Zikmund · Accepted Answer · 2018-12-09 10:31:42Z

1

Just have your textblocks created in a list. So, you can manipulate easily with indexed forloop.

List<string> menuPages = new List<string>() { "Home", "Media", "Settings" };
List<TextBlock> textBlocks = new List<TextBlock>();

public MainPage()
{
    this.InitializeComponent();
    createHeaders();
}

private void createHeaders()
{
    for (int i = 0; i < menuPages.Count; i++)
    {
        TextBlock iheader = new TextBlock();
        iheader.Name = menuPages[i];
        iheader.Text = menuPages[i];              
        iheader.FontSize = 32;
        textBlocks.Add(iheader);
        Stacky.Children.Add(iheader); 
    }
}

private void change_Click(object sender, RoutedEventArgs e)
{
    for (int i = 0; i < textBlocks.Count; i++)
    {
        textBlocks[i].Text = "foo";
    }
}

edited Dec 9, 2018 at 10:31

Martin Zikmund

39.2k7 gold badges74 silver badges95 bronze badges

answered Dec 9, 2018 at 5:09

Vignesh

1,8922 gold badges12 silver badges28 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

user3843874 Over a year ago

Thank you! It seems so obvious now making a second list but I looked past that as I figured it wouldn't register. Very pleased to have learnt this :)

Martin Zikmund · Accepted Answer · 2018-12-09 10:31:10Z

1

If the StackPanel only contains the TextBlock elements you are adding dynamically, you can access them this way as well:

foreach (var textBlock in Stacky.Children.OfType<TextBlock>())
{
   textBlock.Text = "something";
}

This approach uses the OfType<T> LINQ extension method which filters the input collection by the specified type, so it only returns those children of Stacky that are a TextBlock.

If you have more content, in the StackPanel, then @Vignesh G's answer is the way to go.

answered Dec 9, 2018 at 10:31

Martin Zikmund

39.2k7 gold badges74 silver badges95 bronze badges

1 Comment

user3843874 Over a year ago

Didn't quite address my need for indexing so I ended up using Vignesh's solution. But thank you! It did help!

Collectives™ on Stack Overflow

C# (UWP) - Access object dynamically from string-variable

2 Answers 2

1 Comment

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related