如何调用类表单dart库字符串或文件

发布时间：2020-12-14 23:22:51 所属栏目：资源来源：网络整理

导读：谁调用类表单dart库字符串或文件？例如 for-load.dart文件 class TestLoad { void requestHandler(){ }} 然后是main.dart文件 main(){ //this get load lib var lib = currentMirrorSystem().libraries[Uri.parse('dart:core')]; //who to invoke class for

谁调用类表单dart库字符串或文件？

例如

for-load.dart文件

class TestLoad {
  void requestHandler(){
  }
}

然后是main.dart文件

main(){
   //this get load lib
   var lib = currentMirrorSystem().libraries[Uri.parse('dart:core')];
   //who to invoke class form TestLoad or for-load.dart? 
   //like java Class.forName('TestLoad'),nodejs require('for-load')
}

谢谢！

解决方法

这些符号是要动态调用的类的库,类和构造函数的名称

foo.dart

library foo_library;

class Foo {
  String bar;
}

invoke_class.dart

library new_instance_test;

import "dart:mirrors";
import "foo.dart";

int main() {
  // These symbols are the names of the Library,the Class and the constructor for the Class that you want to dynamically load
  final Symbol librarySymbol = const Symbol("foo_library");
  final Symbol classSymbol = const Symbol("Foo");
  final Symbol constructorSymbol = const Symbol("");

  MirrorSystem mirrorSystem = currentMirrorSystem();

  // Get LibraryMirror for Library foo_library.
  // It returns an iterator,get the first LibraryMirror
  LibraryMirror libraryMirror = mirrorSystem.findLibrary(librarySymbol).first;

  // Get ClassMirror for Class Foo
  ClassMirror classMirror = libraryMirror.declarations[classSymbol];

  // Get the InstanceMirror using the default constructor
  InstanceMirror testClassInstanceMirror = classMirror.newInstance(constructorSymbol,[]);

  //Get the reflectee object from the InstanceMirror
  Foo foo = testClassInstanceMirror.reflectee;

  //Set bar and print it
  foo.bar = "foobar";
  print(foo.bar);
}

（编辑：李大同）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!