Reflection method to Draw shape in C# winform

I have a blank method

void DrawShape(Graphics g, int x, int y){

}

I want to pass the "method body" as a string on runtime, to draw a shape by my code, ex:

y =0;
while(x<100){
 x++;
 g.drawRectangle(rec1, x,y);
}

and the method will execute like:

void DrawShape(Graphics g, int x, int y){
    y =0;
    while(x<100){
     x++;
     g.drawRectangle(rec1, x,y);
    }
}

It's will be wonderful, but I don't know how to do that. Any help appreciated