在使用jQuery時候，我們經常會看到或者使用到方法鏈，例如：
$("#p1").css("color","red").slideUp(2000).slideDown(2000);
這段代碼的意思是選擇器選擇id為p1的html標簽，顏色變紅，之后slideup，再slidedown。
自然是可以將這幾個方法分開寫，但是不分開的話不僅有很好的易讀性，代碼量也會有減少，那么何樂而不為？
這種調用函數(shù)的方式在jQuery中稱為“Chaining”，原理也很簡單：能夠chaining的方法調用后返回對象本身即可。
下面用java代碼做個演示：
不使用chaining：
Persion.java：
public class Persion {
private int id;
private String name;
private String phoneNumber;
private String address;
public Persion() {
}
public void setId(int id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setPhoneNumber(String phoneNumber) {
this.phoneNumber = phoneNumber;
}
public void setAddress(String address) {
this.address = address;
}
public void printId() {
System.out.println(this.id);
}
public void printName() {
System.out.println(this.name);
}
public void printPhoneNumber() {
System.out.println(this.phoneNumber);
}
public void printAddress() {
System.out.println(this.address);
}
}
Test.java：
public class Test {
public static void main(String[] args) {
Persion persion1 = new Persion();
persion1.setId(3);
persion1.setName("John");
persion1.setPhoneNumber("1111111");
persion1.setAddress("US");
persion1.printId();
persion1.printName();
persion1.printPhoneNumber();
persion1.printAddress();
}
}
使用chaining：
Persion.java：
public class Persion {
private int id;
private String name;
private String phoneNumber;
private String address;
public Persion() {
}
public Persion setId(int id) {
this.id = id;
return this;
}
public Persion setName(String name) {
this.name = name;
return this;
}
public Persion setPhoneNumber(String phoneNumber) {
this.phoneNumber = phoneNumber;
return this;
}
public Persion setAddress(String address) {
this.address = address;
return this;
}
public Persion printId() {
System.out.println(this.id);
return this;
}
public Persion printName() {
System.out.println(this.name);
return this;
}
public Persion printPhoneNumber() {
System.out.println(this.phoneNumber);
return this;
}
public Persion printAddress() {
System.out.println(this.address);
return this;
}
}
Test.java：
public class Test {
public static void main(String[] args) {
Persion persion1 = new Persion();
persion1.setId(3).setName("John")
.setPhoneNumber("1111111").setAddress("US");
persion1.printId()
.printName()
.printPhoneNumber()
.printAddress();
}
}
好詭異的感覺~哈哈！
