今天查bug的时候,遇到一个问题,一个Dictionary<int[],string>数据结构,在使用key取它的value时: var tempVar = _dic[key]; 发生崩溃.跟进去看看,发现不对啊,key是有的啊,怎么回事?然后并不可能是VS的问题.仔细查了才发现,原来用作索引的key,并不是Dictionary里的keys里的key. 简单地说,就是Dictionary里用1,2,3作为key,而传入的key是:1',2',3'.这样当然是找不到的.由此,引发的想到引用类型和…

public void moveCircle(Circle circle, int deltaX, int deltaY) { // code to move origin of circle to x+deltaX, y+deltaY circle.setX(circle.getX() + deltaX); circle.setY(circle.getY() + deltaY); // code to assign a new reference to circle circle = new…

Python文档中有一段话: Remember that arguments are passed by assignment in Python. Since assignment just creates references to objects, there’s no alias between an argument name in the caller and callee, and so no call-by-reference per se. 我们常说参数的传递分为按值传递与按引…

1.Optional and Named Parameters calls these methods can optionally not specify some of the arguments, thereby accepting the default values. when you call a method, you can specify arguments by using the name of their parameters. When you pass argumen…

ava没有引用传递只有按值传递,没有引用传递只有按值传递,值传递. 通过下面代码解释: 1 public class Test { 2 public static void main(String[] args ){ 3 int var = 1 ; 4 f(var) ; 5 System.out.println(var) ; 6 } 7 public static void f(int newVar ){ 8 newVar = 2 ; 9 } 10 } 执行结果: 1 分析: 当执行 int v…

前言   虽然在.Net Framework 中我们不必考虑内在管理和垃圾回收(GC),但是为了优化应用程序性能我们始终需要了解内存管理和垃圾回收(GC).另外,了解内存管理可以帮助我们理解在每一个程序中定义的每一个变量是怎样工作的.   简介   这篇文章我们将介绍一些方法参数传递行为在堆与栈中的影响.前几节我们介绍了堆与栈的基本工作原理,程序执行时值类型与引用类型在堆栈中的存储.另外,我们已经介绍了一些关于指针的基本知识.这一节中参数传递对堆栈的影响很重要,下面会慢慢道来.   参数,大画面…

函数的参数传递定义:在调用一个函数时,将实参传递给形参. C++中函数的参数传递有按值传递.地址传递和引用传递3种方式.注意:地址也是一种值,按值传递和按地址传递都是单向的值传递方式,即形参都不会回传给实参.但是由于地址的特殊性,地址传递可以间接地改变实参的值,所以分开讨论. 一.按值传递 函数本身不对实参进行操作. #include<iostream> using namespace std; void swap(int,int);//函数声明 void main() { ,b=; swap…

原文出处:http://vim.wikia.com/wiki/Accessing_the_system_clipboard Please review this tip: This tip was imported from vim.org and needs general review. You might clean up comments or merge similar tips. Add suitable categories so people can find the tip.…

原文 关于C#你应该知道的2000件事 下面列出了迄今为止你应该了解的关于C#博客的2000件事的所有帖子. 帖子总数= 1,219 大会 #11 -检查IL使用程序Ildasm.exe d #179 - 什么是大会? #180 - CLR按需加载程序集 #485 - 项目参考和附属组件 #486 - 忽略不必要的项目引用 #705 - 应用程序和类库 #706 - 应用程序域启用应用程序隔离 基本 #1 - Main()签名的样子 #2 - 最小的C#程序 #3 - 谁设计了C#? #4 -…

java没有引用传递只有按值传递,没有引用传递只有按值传递,值传递.因为Primitive类型的值不能改变,所以method不能更改调用方传的primitive 值.因为method更改的是Primitive变量的copy,所以method的更改,调用方是不知道的 因为Reference Data Type的内存地址不能被method中操作更改,所以调用方中Reference Data 对象中的状态 也发生变化.因为method操作的对象,与调用方是相同的,即调用方是知道method中的更改的…

Trails Covering the Basics   1 Getting Started 1.1 The Java Technology Phenomenon 1.1.1 About the Java Technology    The Java Programming Language     ​​   Figure 1 an overview of the software development process     java文件以.java作为后缀 源文件被javac compil…

首先解释下为什么有时候需要bind. 我们可以用bind从函数T add(T a, T b)造出个inc()来,即把b写死为1.这个例子本身比较傻,但有不傻的应用. template<typename T> T add(T a, T b) { return a + b; } template<typename T> auto get_inc() { T b = 1; return bind(add<T>, std::placeholders::_1, b); } std…

来源于:https://developers.google.com/web/tools/chrome-devtools/console/command-line-reference The Command Line API contains a collection of convenience functions for performing common tasks: selecting and inspecting DOM elements, displaying data in read…

1. Primitive Types        Any data types the compiler directly supports are called primitive types.        Primitive types map directly to types existing in the Framework Class Library (FCL).        For the types that are compliant with the Common La…

Reference Genome Components 1. GRCh38 is special because it has alternate contigs that represent population haplotypes. Don't know alternate contig from alternate dimension? Spend five minutes now to review terminology in our Dictionary entryReferenc…

Computer Science An Overview _J. Glenn Brookshear _11th Edition_C Note that passing parameters by value protects the data in the calling unit from being mistakenly altered by a poorly designed procedure. For example, if the calling unit passed an emp…

1. Introduction The Springfox suite of java libraries are all about automating the generation of machine and human readable specifications for JSON APIs written using the spring family of projects. Springfox works by examining an application, once, a…

1.Programming Language Primitive Types primitive types:Any data types the compiler directly supports. Primitive types map directly to types existing in the Framework Class Library (FCL). use the FCL type names and completely avoid the primitive type…

Silverlight If the target managed property or input parameter is strongly typed (that is, not typed as an object), Silverlight attempts to convert the JavaScript object to the corresponding .NET Framework object. If the conversion fails (because of m…

参数传递          函数参数的传递是初始化语义:用调用者的实参去初始化函数的形参,如果参数是对象,需要调用该类的拷贝构造函数,如果没有显式定义的拷贝构造函数,则执行默认的按成员拷贝          返回值传递          函数返回值的传递内容稍多,示例代码: TestClass get_test_obj() { TestClass ret_obj(200): return ret_obj; } void user() { TestClass obj: obj = get_test…

Part 1 http://techmytalk.com/2014/01/24/java-interview-reference-guide-part-1/ Posted on January 24, 2014 by Nitin Kumar JAVA Object Oriented Concepts Java in based on Object Oriented concepts, which permits higher level of abstraction to solve any p…

整理日: 2015年3月18日 引用(reference)和指针(pointer)是学C++过程中最令人头疼的问题,常常不知道什么时候用哪个合适,又常常弄混.找到Dan Saks的这篇文章,讲的很清楚,强烈推荐,所以翻译一下供大家参考. 以下译自Dan Saks的文章 References vs. Pointers 了解引用reference与指针pointer到底有什么不同可以帮助你决定什么时候该用reference,什么时候该用pointer. 在C++ 中,reference在很多方面与指…

n the previous lessons, we used this tool to up level variable to refer to the Redux chore. The components that access this chore, such as the container components, read this straight from it, subscribe to this chore, and dispatch actions on this cho…

===================== Model field reference ===================== .. module:: django.db.models.fields :synopsis: Built-in field types. .. currentmodule:: django.db.models This document contains all the API references of :class:Field including the fie…

Skip Headers Oracle Global Finanicals Oracle Global Financials Technical Reference Manual Release 11i       European Region (EMEA) Flexfields European flexfields are included in the setup and transaction windows of Oracle General Ledger, Payables, an…

Preface Validating data is a common task that occurs throughout all application layers, from the presentation to the persistence layer. Often the same validation logic is implemented in each layer which is time consuming and error-prone. To avoid dup…

1. Introduction 1.1. About 1.2. Sphinx features 1.3. Where to get Sphinx 1.4. License 1.5. Credits 1.6. History 2. Installation 2.1. Supported systems 2.2. Compiling Sphinx from source 2.2.1. Required tools 2.2.2. Compiling on Linux 2.2.3. Known comp…

Configuration Reference This project is sponsored by  #Global CLI Config Some global configurations for @vue/cli, such as your preferred package manager and your locally saved presets, are stored in a JSON file named .vuerc in your home directory. Yo…

/// bugs code with comments #include <iostream> #include <memory> #include <unordered_map> using namespace std; class A { public: A(const std::unordered_map<int, int > &ref) : ref_m(ref) {} void test1(int index) { // std::cout…

JavaScript : Array assignment creates reference not copy 29 May 2015 Consider we have an array var a = [1,2,3,4]; and we assign var b = a; then b not a copy of a, b is a pointer to a. So if you make any changes on b will have effect on a as well. Her…