如何:在运行时创建位图 (Visual C#)
更新:2007 年 11 月
此示例创建并填充 Bitmap 对象,然后在 PictureBox 控件中显示该对象。若要运行此示例,请创建一个 Windows 窗体应用程序项目,并将 PictureBox 控件从“工具箱”拖到窗体上。图片框的大小并不重要;它将自动调整自身大小以适合位图。将 CreateBitmap 方法粘贴到 Form1 类中,然后从 Form1_Load 事件处理程序方法中调用它。
示例
void CreateBitmap()
{
const int colWidth = 10;
const int rowHeight = 10;
System.Drawing.Bitmap checks = new System.Drawing.Bitmap(
colWidth * 10, rowHeight * 10);
// The checkerboard consists of 10 rows and 10 columns.
// Each square in the checkerboard is 10 x 10 pixels.
// The nested for loops are used to calculate the position
// of each square on the bitmap surface, and to set the
// pixels to black or white.
// The two outer loops iterate through
// each square in the bitmap surface.
for (int columns = 0; columns < 10; columns++)
{
for (int rows = 0; rows < 10; rows++)
{
// Determine whether the current sqaure
// should be black or white.
Color color;
if (columns % 2 == 0)
color = rows % 2 == 0 ? Color.Black : Color.White;
else
color = rows % 2 == 0 ? Color.White : Color.Black;
// The two inner loops iterate through
// each pixel in an individual square.
for (int j = columns * colWidth; j < (columns * colWidth) + colWidth; j++)
{
for (int k = rows * rowHeight; k < (rows * rowHeight) + rowHeight; k++)
{
// Set the pixel to the correct color.
checks.SetPixel(j, k, color);
}
}
}
}
}
编译代码
此示例需要:
- 对 System 命名空间的引用。
可靠编程
以下情况可能会导致异常:
- 试图在位图的界限之外设置像素。