注入一个类到另一个类
我有一个类InjectedClass用方法someMethod。班级需要三个参数。我需要另一个类的方法输出,Myclass。基本上,我需要通过Myclass中的构造函数传递相同的三个参数给注入类,因为它返回一些数据。注入一个类到另一个类
问题是我得到一个错误,指出在Myclass构造函数中的第四个参数(注入类)预计是一个injectClass的实例,但它是空的!见示例。
我认为问题是Injected类正在初始化没有参数,因此不初始化,因此是空的。另外,如果我尝试将该课程直接注入myfunction方法,我会得到或多或少的相同结果。我如何解决这个烂摊子?
class Myclass {
private $var1;
private $var2;
private $var3;
private $injectedclass;
public function __construct($var1, $var2, $var3, InjectedClass $injectedclass)
{
$this->var1 = $var1;
$this->var2 = $var2;
$this->var3 = $var3;
$this->injectedclass = $injectedclass;
}
public function myfunction()
{
return $this->injectedclass($this->var1, $this->var2, $this->var3)->someMethod();
}
}
class InjectedClass {
private $var1;
private $var2;
private $var3;
public function __construct($var1, $var2, $var3)
{
$this->var1 = $var1;
$this->var2 = $var2;
$this->var3 = $var3;
}
public function someMethod()
{
// do stuff
}
}
MyClass只需要构造中的一个参数 - InjectedClass instansce,它已准备好工作。即
$injected = new Injected($var1, $var2, $var);
$my = new MyClass($injected);
$my->myfunction(); // will work correctly now
我会重新考虑如何尝试使用依赖注入。最简单的方法就是在InjectedClass中创建setter,并在设置构造中的类变量时设置它们。喜欢的东西:
class Myclass {
private $var1;
private $var2;
private $var3;
private $injectedclass;
public function __construct($var1, $var2, $var3, InjectedClass $injectedclass)
{
$this->var1 = $var1;
$this->var2 = $var2;
$this->var3 = $var3;
$this->injectedclass = $injectedclass;
$this->injectedclass->setParams($this->var1, $this->var2, $this->var3);
}
public function myfunction()
{
return $this->injectedclass($this->var1, $this->var2, $this->var3)->someMethod();
}
}
class InjectedClass {
private $var1;
private $var2;
private $var3;
public function setParams($var1, $var2, $var3) {
$this->var1 = $var1;
$this->var2 = $var2;
$this->var3 = $var3;
}
public function someMethod()
{
// do stuff
}
}
当然,你可以清理它了一点,但通过执行注射这种方式,您应该能够避免你所面临的问题。
一切都取决于你想要达到的目标,但基本上在
public function myfunction()
{
return $this->injectedclass($this->var1, $this->var2, $this->var3)->someMethod();
}
你不需要通过这些参数,因为$this->injectedclass
已经是对象,该对象已初始化其属性。因此,代码应该是这样的:
class Myclass {
private $var1;
private $var2;
private $var3;
private $injectedclass;
public function __construct($var1, $var2, $var3, InjectedClass $injectedclass)
{
$this->var1 = $var1;
$this->var2 = $var2;
$this->var3 = $var3;
$this->injectedclass = $injectedclass;
}
public function myfunction()
{
return $this->injectedclass->someMethod();
}
}
class InjectedClass {
private $var1;
private $var2;
private $var3;
public function __construct($var1, $var2, $var3)
{
$this->var1 = $var1;
$this->var2 = $var2;
$this->var3 = $var3;
}
public function someMethod()
{
// do stuff
echo $this->var1.' '.$this->var2.' '.$this->var3."<br />";
}
}
$m = new Myclass(1,2,3, new InjectedClass(1,2,3));
$m->myFunction();
但是当你看到当您创建Myclass
例如,你需要传递的参数1,2,3
既Myclass
和InjectedClass
如果这些值是相同的,这可能是不是很方便。
所以你可以改变你的代码:
class Myclass {
private $var1;
private $var2;
private $var3;
private $injectedclass;
public function __construct($var1, $var2, $var3, InjectedClass $injectedclass)
{
$this->var1 = $var1;
$this->var2 = $var2;
$this->var3 = $var3;
$this->injectedclass = $injectedclass;
$this->injectedclass->setParams($var1, $var2, $var3);
}
public function myfunction()
{
return $this->injectedclass->someMethod();
}
}
class InjectedClass {
private $var1;
private $var2;
private $var3;
public function setParams($var1, $var2, $var3)
{
$this->var1 = $var1;
$this->var2 = $var2;
$this->var3 = $var3;
}
public function someMethod()
{
// do stuff
echo $this->var1.' '.$this->var2.' '.$this->var3."<br />";
}
}
$m = new Myclass(1,2,3, new InjectedClass());
$m->myFunction();
所以你传递参数只能Myclass
并将其设置参数InjectedClass
。但是这种方法会导致即使您创建InjectedClass
类的对象,您也需要运行setParams
方法来设置参数,因此它不是最佳解决方案。
更好的将是:
class Myclass {
private $var1;
private $var2;
private $var3;
private $injectedclass;
public function __construct(InjectedClass $injectedclass)
{
$this->injectedclass = $injectedclass;
list ($this->var1, $this->var2, $this->var3) = $this->injectedclass->getParams();
}
public function myfunction()
{
return $this->injectedclass->someMethod();
}
}
class InjectedClass {
private $var1;
private $var2;
private $var3;
public function __construct($var1, $var2, $var3)
{
$this->var1 = $var1;
$this->var2 = $var2;
$this->var3 = $var3;
}
public function getParams() {
return array ($this->var1, $this->var2, $this->var3);
}
public function someMethod()
{
// do stuff
echo $this->var1.' '.$this->var2.' '.$this->var3."<br />";
}
}
$m = new Myclass(new InjectedClass(1,2,3));
$m->myFunction();
其中InjectedClass
对象可以返回这些参数的Myclass
反对。
你怎么调用'Myclass'? – cmorrissey 2014-09-19 20:21:18
$ myclass = new Myclass($ var1,$ var2,$ var3); – Rastur 2014-09-19 20:23:56