Try this code:
using System;
using System.Drawing;
using System.Windows.Forms;
namespace Test
{
public partial class Form1 : Form
{
bool mouseHover;
int width;
int height;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
timer1.Interval = 25;
timer1.Tick += timer1_Tick;
width = pictureBox1.Width;
height = pictureBox1.Height;
timer1.Start();
}
void timer1_Tick(object sender, EventArgs e)
{
if (mouseHover)
{
pictureBox1.Width += (pictureBox1.Width < 100) ? 5 : 0;
pictureBox1.Height += (pictureBox1.Height < 100) ? 5 : 0;
}
else
{
pictureBox1.Width += (pictureBox1.Width > width) ? -5 : 0;
pictureBox1.Height += (pictureBox1.Height > height) ? -5 : 0;
}
}
private void pictureBox1_MouseEnter(object sender, EventArgs e)
{
mouseHover = true;
}
private void pictureBox1_MouseLeave(object sender, EventArgs e)
{
mouseHover = false;
}
}
}
You can adjust the interval to how you like it, but increasing at 5 pixels horizontally/vertically every 25 milliseconds is pretty smooth. You need to set the initial height and width so you can go back to that size after the mouse leaves the picture box. I use the null coalescing operator so you don't have to stop the timer. As long as the condition on the left side of the ?
is true, it will evaluate to the value on the left side of the :
. When the condition is false, it evaluates to the right side of the :
.