请问下面的:this(null,0,url_link)怎么理解

[blackjunes]

public class Url
{
private Url father_url = null;
private int current_depth = 0;
private Uri url_link ;


public Url(Uri url_link):this(null,0,url_link)
{

}

public Url(Url father_url, int current_depth, Uri url_link)
{
this.father_url = father_url;
this.current_depth = current_depth;
this.url_link = url_link;
}
}

[nonocast]

构造函数问题
Url(Uri url_link):this(null,0,url_link)就是会自动调用另一个构造
Url(Url father_url, int current_depth, Uri url_link)，传入参数为null,0,url_link

[使我做你和平之子]

这个叫做constructor chaining，就是指定了this(null,0,url_link)后，执行完Url(Uri url_link)之后，就执行Url(Url father_url, int current_depth, Uri url_link)