初识C#

2022-08-25 08:52 148阅读 0赞

刚刚接触c\#，有很多知识点觉得很熟悉，又有很多名词从来没听过，整的满头雾水，所以先理清思路再继续学习。

首先c\#是一门编程语言，它是面向对象的、运行于.net fromwork之上的高级程序设计语言。c\#继承了c和c++的强大功能同时还去除了一些他们的复杂性。

之前我们学过vb编程，所以对与编程语言并不算陌生，不同的编程语言也有很多知识都是相通的，所以学习过程中有些知识还是便于理解的。但c\#与vb同时也有许多不同之处：

**1.声明变量**

dim a as string

string a

分别是vb和c\#中声明变量的格式，他们都是声明了a作为一个字符串变量，相比来看c\#中就要比vb简单得多。

**2.定义常量**

在vb中一次只能定义一个常量，而c\#中“枚举”一次可以定义一组常量，枚举以enum关键字声明。

**3.语法**

**c\#语法：                                                vb语法：**

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  <tr style="margin:0px; padding:0px; border:0px currentColor"> 
   <td colspan="2" style="margin:0px; padding:0px; border:0px currentColor"><span style="font-family:SimSun; font-size:14px">&nbsp;<strong>For 循环：</strong></span></td> 
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   <td style="margin:0px; padding:0px; border:0px currentColor; background-color:white"> 
    <div style="margin:0px; padding:0px; border:0px currentColor"> 
     <span style="font-family:SimSun; font-size:14px">&nbsp; for (int i=0; i&lt;3; i++) a(i) = "test";</span> 
    </div> </td> 
   <td style="margin:0px; padding:0px; border:0px currentColor; background-color:white"> 
    <div style="margin:0px; padding:0px; border:0px currentColor"> 
     <span style="font-family:SimSun; font-size:14px">&nbsp;&nbsp;&nbsp; &nbsp;Dim I As Integer For I = 0 To 2 a(I) = "test" Next</span> 
    </div> </td> 
  </tr> 
  <tr style="margin:0px; padding:0px; border:0px currentColor"> 
   <td colspan="2" style="margin:0px; padding:0px; border:0px currentColor"><span style="font-family:SimSun; font-size:14px">&nbsp;<strong>While 循环：</strong></span></td> 
  </tr> 
  <tr style="margin:0px; padding:0px; border:0px currentColor"> 
   <td style="margin:0px; padding:0px; border:0px currentColor; background-color:white"> 
    <div style="margin:0px; padding:0px; border:0px currentColor"> 
     <span style="font-family:SimSun; font-size:14px">&nbsp; int i = 0; while (i&lt;3) { Console.WriteLine(i.ToString()); i += 1; }</span> 
    </div> </td> 
   <td style="margin:0px; padding:0px; border:0px currentColor; background-color:white"> 
    <div style="margin:0px; padding:0px; border:0px currentColor"> 
     <span style="font-family:SimSun; font-size:14px">&nbsp;&nbsp;&nbsp;&nbsp; Dim I As Integer I = 0 Do While I &lt; 3 Console.WriteLine&nbsp;&nbsp;(I.ToString()) I = I + 1 Loop</span> 
    </div> </td> 
  </tr> 
  <tr style="margin:0px; padding:0px; border:0px currentColor"> 
   <td colspan="2" style="margin:0px; padding:0px; border:0px currentColor"><span style="font-family:SimSun; font-size:14px">&nbsp;<strong>字符串联：</strong></span></td> 
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  <tr style="margin:0px; padding:0px; border:0px currentColor"> 
   <td style="margin:0px; padding:0px; border:0px currentColor; background-color:white"> 
    <div style="margin:0px; padding:0px; border:0px currentColor"> 
     <span style="font-family:SimSun; font-size:14px">&nbsp; String s1; String s2 = "hello"; s2 += " world"; s1 = s2 + " !!!";</span> 
    </div> </td> 
   <td style="margin:0px; padding:0px; border:0px currentColor; background-color:white"> 
    <div style="margin:0px; padding:0px; border:0px currentColor"> 
     <span style="font-family:SimSun; font-size:14px">&nbsp;&nbsp;&nbsp; &nbsp;Dim s1, s2 As String s2 = "hello" s2 &amp;= " world" s1 = s2 &amp; " !!!"</span> 
    </div> </td> 
  </tr> 
 </tbody> 
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