C＃在Windows Phone应用程序中按按钮更改图像

Question

I know how to put an image into a picture box and have it show up with the press of a button, but how would I change the image with the press of the same button? Here's the code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Navigation;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;
using System.Windows.Media.Imaging;

namespace HuntersApp
{

    public partial class TracksPage : PhoneApplicationPage
    {
        public TracksPage()
        {
            InitializeComponent();
        }
        string[] imageArray = new string[] { "/Images" };
        private void nextButton_Click(object sender, RoutedEventArgs e)
        {   

        }

        private void previousButton_Click(object sender, RoutedEventArgs e)
        {
            tracksImage.Source = new BitmapImage(new Uri("/Images/cottontail55.jpg",UriKind.Relative));
        }
    }
}

Answer 1

Add an array of all the images in your class and a variable that increments like this:

public partial class TracksPage : PhoneApplicationPage
{
    string[] imagePaths = new string[] { "/path/to/image1.jpg",
                                         "/path/to/image2.jpg",
                                         "/path/to/image3.jpg",
                                         "/path/to/image4.jpg",
                                         "/path/to/image5.jpg" };
    int i = 0;
    .
    .
    .

Then in your previousButton_Click() function:

private void previousButton_Click(object sender, RoutedEventArgs e)
{
    tracksImage.Source = new BitmapImage(new Uri(imagePaths[i], UriKind.Relative));

    i = i == 4 ? 0 : i + 1; // Change 4 to the number of images you have + 1. In this example, I assume 5 images.
}

Answer 2

Assuming that you want to keep going to next image on nextButton_Click , here's how you can do it.

string[] imageArray = new string[] { "url1", "url2" }; //This array contains URI strings
private counter = 0; //This denotes index of array

private void nextButton_Click(object sender, RoutedEventArgs e)
{   
    tracksImage.Source = new BitmapImage(new Uri(imageArray[counter], UriKind.Relative));
    counter++;
}

Of course, you will have to take care of counter not exceeding the length of array.

Also, bonus: please stick to .Net naming conventions. Names are written in pascal case instead of camel case here. So, it would be TracksImage and NextButton and so on! Here are more details.