创建一个简单窗口， 按下鼠标左键，同时按下键盘上的ctrl键，拖动鼠标，在用户区上画出一个矩形，矩形左上角以初始按下鼠标的点，右下角为鼠标当前位置，放开鼠标，窗口用户区显示一个最后的矩形。按下键盘的‘l’(英文字母L的小写)，矩形放大，按下‘s’键，矩形缩小，并能用方向键实现所画矩形按相应方向移动。

可以使用以下代码来创建简单窗口并绘制矩形：

import tkinter as tk

class RectDrawer:
    def __init__(self):
        self.root = tk.Tk()
        self.canvas = tk.Canvas(self.root, bg="white")
        self.canvas.pack(fill=tk.BOTH, expand=1)
        
        self.is_drawing = False
        self.rect = None
        self.init_pos = None
        
        self.canvas.bind("<Button-1>", self.on_left_click)
        self.canvas.bind("<B1-Motion>", self.on_dragging)
        self.canvas.bind("<ButtonRelease-1>", self.on_left_release)
        
        self.canvas.focus_set()
        self.canvas.bind("<Key>", self.on_key_press)

    def on_left_click(self, event):
        if event.state & 0x4:  # Check if Ctrl key is pressed
            self.is_drawing = True
            self.init_pos = (event.x, event.y)
            
    def on_dragging(self, event):
        if self.is_drawing:
            x0, y0 = self.init_pos
            x1, y1 = event.x, event.y
            if self.rect:
                self.canvas.delete(self.rect)
            self.rect = self.canvas.create_rectangle(
                x0, y0, x1, y1, outline="black")
            
    def on_left_release(self, event):
        if self.is_drawing:
            self.is_drawing = False
            x0, y0 = self.init_pos
            x1, y1 = event.x, event.y
            if self.rect:
                self.canvas.delete(self.rect)
            self.rect = self.canvas.create_rectangle(
                x0, y0, x1, y1, outline="black", fill="white")
            
    def on_key_press(self, event):
        if event.char.lower() == "l":  # Enlarge the rectangle
            if self.rect:
                coords = self.canvas.coords(self.rect)
                x0, y0, x1, y1 = coords
                self.canvas.delete(self.rect)
                self.rect = self.canvas.create_rectangle(
                    x0-10, y0-10, x1+10, y1+10, outline="black", fill="white")
        elif event.char.lower() == "s":  # Shrink the rectangle
            if self.rect:
                coords = self.canvas.coords(self.rect)
                x0, y0, x1, y1 = coords
                self.canvas.delete(self.rect)
                self.rect = self.canvas.create_rectangle(
                    x0+10, y0+10, x1-10, y1-10, outline="black", fill="white")
        elif event.keysym in ("Up", "Down", "Left", "Right"):  # Move the rectangle
            if self.rect:
                coords = self.canvas.coords(self.rect)
                dx, dy = 0, 0
                if event.keysym == "Up":
                    dy = -10
                elif event.keysym == "Down":
                    dy = 10
                elif event.keysym == "Left":
                    dx = -10
                elif event.keysym == "Right":
                    dx = 10
                x0, y0, x1, y1 = coords
                self.canvas.delete(self.rect)
                self.rect = self.canvas.create_rectangle(
                    x0+dx, y0+dy, x1+dx, y1+dy, outline="black", fill="white")
        
    def run(self):
        self.root.mainloop()

if __name__ == "__main__":
    app = RectDrawer()
    app.run()

当用户按下鼠标左键加上Ctrl键时，程序会记录下初始位置。当用户拖动鼠标时，程序不断更新矩形的位置和大小。当用户松开鼠标时，程序最终确定矩形的位置和大小。当用户按下键盘上的'l'键时，程序会把矩形放大。当用户按下's'键时，程序会把矩形缩小。当用户按下方向键时，程序会把矩形按相应方向移动。