WanAkiko.

若两个变量的类型相兼容(同属于数字)，可以使用自动类型转换或者强制类型转换；而当两个变量的类型不兼容时，例如 string 与 int 不相兼容，此时可使用 Convert 进行类型转换。 int Convert.ToInt32(string value); * 此方法可将字符串类型的数字转换为整数型数字，但有可能转换失败，其抛出异常时需要手动处理。 void int.Parse(string value); * 此方法可将字符串类型的数字转换为整数型数字，Convert.T

using System;using System.IO;using System.Collections.Generic;namespace Demo{ class Program { static void Main(string[] args) { // 声明文件读取流并指定文件位置 StreamReader reader = new StreamReader(@"C:\Users\Adminis

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Windows.Forms;namespace VerCode{ public partial cl

using System;using System.Threading;using System.Windows.Forms;namespace Ernie{ public partial class MainForm : Form { public MainForm() { InitializeComponent(); } bool flag = false; privat

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Windows.Forms;using System.IO;using System.Media;namespace Demo08_MusicPlayer{

// 获取指定文件夹中所有文件的全路径string[] picPathArr = Directory.GetFiles(@"D:\Aggregate_Data\Documents\MyFiles\MyPicture\其他图片");int picIndex = 0; // 图片路径下标/// <summary>/// 从本地资源管理其中加载图片资源/// </summary>/// <param name="sender"></param>//

private void 显示子窗体ToolStripMenuItem_Click(object sender, EventArgs e){ SubForm1 sb1 = new SubForm1(); sb1.Show(); sb1.MdiParent = this; SubForm2 sb2 = new SubForm2(); sb2.Show(); sb2.MdiParent = this;}private void 横向排列Too

private void btnSave_Click(object sender, EventArgs e) { using (FileStream fsWrite = new FileStream(@"C:\Users\WanAkiko\Desktop\新建文本文档.txt", FileMode.OpenOrCreate, FileAccess.Write)) { string str = 文本输入框.Text.Trim(); ...

using System;namespace CSharp三次课{ class Program { static void Main(string[] args) { bool shutdown = true; while (shutdown) { Console.Write("\n请输入一个IP地址："); strin

using System;using System.Collections;using System.Collections.Generic;namespace OOP{class Program{static void Main(string[] args){int[] chIndex = new int[] { 1, 2, 3, 4, 5, 6 };for (int i = 0; i <= 4; i += 2){int temp = chIndex[i];chIndex[

using System;namespace CSharp二次课_课后_{ class Program { static void Main(string[] args) { int sum = 1; for (int i = 9; i > 0; i--) { sum = (sum + 1) * 2; Consol

using System;namespace CSharp{ class Program { static void Main(string[] args) { Console.Write("请输入第一个数："); int num01 = int.Parse(Console.ReadLine()); Console.Write("请输入第二个数："); int

using System;namespace CSharp{class Program{static void Main(string[] args){Console.Write(“请输入一段字符：”);char[] cArr = Console.ReadLine().ToCharArray();for (int i = 0; i < cArr.Length; i++){if (cArr[i] >= 65 && cArr[i] <= 90){Con

using System;using System.Collections.Generic;namespace oop05_里式转换{ class Program { static void Main(string[] args) { // is使用示例 Person subStu = new Student(); // Student类继承自Person类 if (subStu

using System;using System.Collections.Generic;namespace oop05_里式转换{ class Program { static void Main(string[] args) { Person[] per = new Person[10]; Random rd = new Random(); for (int i = 0; i

    子类可以赋值给父类：即向上转型，子类对象可以调用父类的成员，但父类对象只能调用自己的成员。    向上转型：子类对象交给父类引用，父类引用指向子类对象。    Eg：Animal an = new Dog();    若父类中装的是子类对象，则可将此父类强转为子类对象：即向下转型，父类引用决定可以调用什么，而子类对象决定具体做什.

① 字符串对象有初始值且不为null时使用：object.Length() == 0     Tips：此方法效率最高但在使用时可能产生异常。② object == string.Empty 和 object == ""     Tips：此两项方法前者的效率要略高于后者，但均逊于object.Length() == 0，使用时不会产生异常。③ 判断字符串对象是否存在以及是否为空：string.IsN

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _37_Ex_Reserve2AndPrime { static void Main(string[] args) { #region 计算整形数组元素的平均值，保留两位小数输出 int[] intArr = {

using DocumentFormat.OpenXml.Drawing.Charts;using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _36_Ex_Function { static void Main(string[] args) { string[] NBA = { "张伯伦"

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _35_Ex_Function { /// <summary> /// 方法练习 /// </summary> /// <param name="args"></param>

将实参列表中与动态参数数组类型一致的元素当做数组元素进行操作，参数数组必须是形参列表中的最后一个参数。using DocumentFormat.OpenXml.Drawing.Diagrams;using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _34_ArgsParams { static void Main(string

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _33_ArgsRef { static void Main(string[] args) { int num01 = 10, num02 = 20; Console.WriteLine("交换前：num01({0

using DocumentFormat.OpenXml.Drawing.Charts;using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _32_Ex_ArgsOut { static void Main(string[] args) { int result;

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _31_Ex_ArgsOut { /// <summary> /// 使用out参数模拟用户登录 /// </summary> /// <param name="args"></param

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _31_ArgsOut { static void Main(string[] args) { int[] numArr = { 1, 2, 3, 4, 5, 6, 7, 8, 9 }; // 当使用out参数接

using DocumentFormat.OpenXml.Spreadsheet;using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _30_ArgsOut { static void Main(string[] args) { int[] numArr = { 1, 2, 3, 4,

using DocumentFormat.OpenXml.Wordprocessing;using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _28_ArrayElements { static void Main(string[] args) { Random rd = new Rand

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _27_Ex_Array { static void Main(string[] args) { string[] letterArr = { "A", "B", "C", "D", "E", "F", "G" };

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _27_Ex_Array { static void Main(string[] args) { string[] nameArr = { "老杨", "老苏", "老周", "老马", "老蒋", "老赵", "老吴", "老华" };

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _26_Array { /// <summary> /// 数组 /// </summary> /// <param name="args"></param> sta

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _25_Structure { /// <summary> /// 性别枚举 /// </summary> public enum EnumGender { 男, 女 } /// <

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ public enum QQstatus { OnLine, QMe, Leave, Busy, PleaseDoNotDisturb, Cloaking, OffLine } class _24_Ex_Enum { static void Main

定义枚举类型：using DocumentFormat.OpenXml.Office2010.Excel;using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ public enum QQStatus { // 枚举QQ状态：在线，Q我吧，离开，忙碌，请勿打扰，隐身，离线 OnLine, QMe, Leave, Bus

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _21_TernaryExpression { static void Main(string[] args) { Random rd = new Random(); // 创建随机器 for (int i = 0

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _18_TypeConvertAndFunction { static void Main(string[] args) { /// /// int Convert.ToInt32(string value);

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _19_Ex_For { static void Main(string[] args) { int[] ageArr = new int[5]; // 定义年龄数组 int times = 1; // 定义计次标

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _17_Ex_For { static void Main(string[] args) { Console.Write("请输入一个目标数："); try {

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _17_Ex_For { static void Main(string[] args) { Console.Write("请指定需要录入的学生个数："); int stuCount = int.Parse(Con

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _17_Ex_For { static void Main(string[] args) { Console.WriteLine("输出普通九九乘法表"); for (int i = 1; i <= 9; i

using System;using System.Collections.Generic;using System.Text;namespace KnowledgePoint{ class _17_Ex_For { static void Main(string[] args) { // 正向for循环：编辑器输入for后再按两下Tab键补齐代码 // 逆向for循环：编辑器输入forr后再按两下Ta