使用Dart中的反射从ClassMirror获取getters和/或attribuites？ [英] Obtain getters and/or attribuites from ClassMirror using reflection in Dart?

问题描述

上一个版本的dart可以使用

获取getters。

$ b

  cm.getters.values 
  

正如此答案中发布的：http://stackoverflow.com/a/14505025/2117440

但实际版本已移除并替换为

  cm.declarations.values 
  

最后一个代码获取所有属性，getter，setter，方法和构造函数。我想知道是否有一种方法只有getters和attributes没有其他方法。

我现在使用的代码是一个：

  importdart：mirrors 
 
 class MyNestedClass {
 String name; 
} 
 class MyClass {
 int i，j; 
 MyNestedClass myNestedClass; 
 int sum（）=> i + j; 
 
 MyClass（this.i，this.j）; 
} 
 
 void main（）{
 MyClass myClass = new MyClass（3，5）
 ..myNestedClass =（new MyNestedClass luis）; 
 print（myClass.toString（））; 
 InstanceMirror im = reflect（myClass）; 
 
 ClassMirror cm = im.type; 
 
映射< Symbol，MethodMirror> instanceMembers = cm.instanceMembers; 
 
 cm.declarations.forEach（（name，declaration）{
 if（declaration.simpleName！= cm.simpleName）//如果不是te构造函数
 print（'$ {MirrorSystem.getName（name）}：$ {im.getField（name）.reflectee}'）; 
}）; 
} 
  

正如你在前面的代码中可以看到的，检查是否不是我需要的构造函数以将declaration.simpleName与cm.simpleName进行比较。直到我明白是无效的，因为我们比较字符串。

总之，我想知道是否有或将是一个更好的方法来解决这个问题。 / p>

解决方案

也许有更好的方法，但这应该提供你需要的

< pre class =lang-dart prettyprint-override> cm.declarations.forEach（（name，declaration）{
VariableMirror field;
if（declaration是VariableMirror）field = declaration ;

MethodMirror方法;
if（声明为MethodMirror）method = declaration;

if（field！= null）{
print ：$ {field.simpleName}'）;
} else if（method！= null&&！method.isConstructor）{
print（'method：$ {method.simpleName}'）;
}
}）;


投射到 VariableMirror 或 MethodMirror 您可以获得更多属性：

字段：

- isConst

- isFinal

- isStatic

方法：

- constructorName

- isConstructor

- isConstConstructor

- isFactoryConstructor

- isGenerativeConstructor

- isGetter

- isOperator

- isRedirecting构造函数

- isRegularMethod

- isSetter

- isStatic

- isSynthetic

Previous version of dart were able to get getters using

cm.getters.values

As is posted in this answer: http://stackoverflow.com/a/14505025/2117440

However actual version was removed that featuread and replaced by

cm.declarations.values

last code gets all attributes, getters, setters, methods and constructor. I would like to know if there is a way to get only "getters and attributes" without others method.

The code that I'm using right now is that one:

import "dart:mirrors";

class MyNestedClass {
  String name;
}
class MyClass {
  int i, j;
  MyNestedClass myNestedClass;
  int sum() => i + j;

  MyClass(this.i, this.j);
}

void main() {
  MyClass myClass = new MyClass(3, 5)
    ..myNestedClass = (new MyNestedClass()..name = "luis");
  print(myClass.toString());
  InstanceMirror im = reflect(myClass);

  ClassMirror cm = im.type;

  Map<Symbol, MethodMirror> instanceMembers = cm.instanceMembers;

  cm.declarations.forEach((name, declaration) {
      if(declaration.simpleName != cm.simpleName) // If is not te constructor
        print('${MirrorSystem.getName(name)}:${im.getField(name).reflectee}');
  });
}

As you can see in previous code to check if is not the constructor I need to compare the declaration.simpleName with cm.simpleName. Which until I understand is inefficient since we are comparing strings.

In conclusion, I would like to know if there is or will be a better way to solve this problem.

解决方案

Maybe there is a better way but this should provide what you need

  cm.declarations.forEach((name, declaration) {
    VariableMirror field;
    if(declaration is VariableMirror) field = declaration;

    MethodMirror method;
    if(declaration is MethodMirror) method = declaration;

    if(field != null) {
      print('field: ${field.simpleName}');
    } else if(method != null && !method.isConstructor){
      print('method: ${method.simpleName}');
    }
  });

After casting to VariableMirror or MethodMirror you can get a lot more properties:

field:
- isConst
- isFinal
- isStatic

method:
- constructorName
- isConstructor
- isConstConstructor
- isFactoryConstructor
- isGenerativeConstructor
- isGetter
- isOperator
- isRedirectingConstructor
- isRegularMethod
- isSetter
- isStatic
- isSynthetic

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