这样的写法有什么优点呢？

[guohuan1816]

新手。请问下下面的构造函数这样写的目的，以及优点是什么？
public Sprite(Texture2D textureImage, Vector2 position, Point frameSize,
int collisionOffset, Point currentFrame, Point sheetSize, Vector2 speed)
: this(textureImage, position, frameSize, collisionOffset, currentFrame,
sheetSize, speed, defaultMillisecondsPerFrame)
{
}

public Sprite(Texture2D textureImage, Vector2 position, Point frameSize,
int collisionOffset, Point currentFrame, Point sheetSize, Vector2 speed,
int millisecondsPerFrame)
{
this.textureImage = textureImage;
this.position = position;
this.frameSize = frameSize;
this.collisionOffset = collisionOffset;
this.currentFrame = currentFrame;
this.sheetSize = sheetSize;
this.speed = speed;
this.millisecondsPerFrame = millisecondsPerFrame;
}

[lihanbing]

相当于把millisecondsPerFrame做为可选参数，c++、c#不支持可选参数，所以写成这样

[暖眸]

顶一楼的。就是这样子的。

[newxdlysk]

1.看起来更清晰
2.可以调用基类的构造函数把this换成base