C++ 类型转换（内置类型,string、char、const char等）

客官°小女子只卖身不卖艺 2022-12-04 07:32 205阅读 0赞

**目录**

类型

转换

全部代码

--------------------

文章适用于已经学了C++语言，对C++类型有一定了解的朋友。对类型转换进行总结，包括内置类型，string，以及由c语言引入的一些类型。

# 类型 #

<table> 
 <tbody> 
  <tr> 
   <th>内置数据类型</th> 
   <th>字节</th> 
   <th>范围</th> 
  </tr> 
  <tr> 
   <td>char</td> 
   <td>1 个字节</td> 
   <td>-128 到 127 或者 0 到 255</td> 
  </tr> 
  <tr> 
   <td>unsigned char</td> 
   <td>1 个字节</td> 
   <td>0 到 255</td> 
  </tr> 
  <tr> 
   <td>signed char</td> 
   <td>1 个字节</td> 
   <td>-128 到 127</td> 
  </tr> 
  <tr> 
   <td>int</td> 
   <td>4 个字节</td> 
   <td>-2147483648 到 2147483647</td> 
  </tr> 
  <tr> 
   <td>unsigned int</td> 
   <td>4 个字节</td> 
   <td>0 到 4294967295</td> 
  </tr> 
  <tr> 
   <td>signed int</td> 
   <td>4 个字节</td> 
   <td>-2147483648 到 2147483647</td> 
  </tr> 
  <tr> 
   <td>short int</td> 
   <td>2 个字节</td> 
   <td>-32768 到 32767</td> 
  </tr> 
  <tr> 
   <td>unsigned short int</td> 
   <td>2 个字节</td> 
   <td>0 到 65,535</td> 
  </tr> 
  <tr> 
   <td>signed short int</td> 
   <td>2 个字节</td> 
   <td>-32768 到 32767</td> 
  </tr> 
  <tr> 
   <td>long int</td> 
   <td>8 个字节</td> 
   <td>-9,223,372,036,854,775,808 到 9,223,372,036,854,775,807</td> 
  </tr> 
  <tr> 
   <td>signed long int</td> 
   <td>8 个字节</td> 
   <td>-9,223,372,036,854,775,808 到 9,223,372,036,854,775,807</td> 
  </tr> 
  <tr> 
   <td>unsigned long int</td> 
   <td>8 个字节</td> 
   <td>0 到 18,446,744,073,709,551,615</td> 
  </tr> 
  <tr> 
   <td>float</td> 
   <td>4 个字节</td> 
   <td>精度型占4个字节（32位）内存空间，+/- 3.4e +/- 38 (~7 个数字)</td> 
  </tr> 
  <tr> 
   <td>double</td> 
   <td>8 个字节</td> 
   <td>双精度型占8 个字节（64位）内存空间，+/- 1.7e +/- 308 (~15 个数字)</td> 
  </tr> 
  <tr> 
   <td>long double</td> 
   <td>16 个字节</td> 
   <td>长双精度型 16 个字节（128位）内存空间，可提供18-19位有效数字。</td> 
  </tr> 
  <tr> 
   <td>wchar_t</td> 
   <td>2 或 4 个字节</td> 
   <td>1 个宽字符</td> 
  </tr> 
 </tbody> 
</table>

字符串

string C++的类

C风格 const char\*、char\*、char\[\]

# 转换 #

C++类型转换主要分为两种：隐式类型转换、显式类型转换（强制类型转换）。

所谓隐式类型转换，是指不需要用户干预，编译器默认进行的类型转换行为。

四种强制类型转换操作符：static\_cast、const\_cast、dynamic\_cast、reinterpret\_cast

还有类的构造方法，类的方法、流等

<table>  类型转换及方法  
 <thead> 
  <tr> 
   <th style="width:559px;">类型转换左转右</th> 
   <th style="width:348px;">方法</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td style="width:559px;">char-&gt;其他内置类型及const char*、char*</td> 
   <td style="width:348px;">隐式转换</td> 
  </tr> 
  <tr> 
   <td style="width:559px;">unsigned char、signed char-&gt;其他内置类型</td> 
   <td style="width:348px;">隐式转换</td> 
  </tr> 
  <tr> 
   <td style="width:559px;">unsigned char、signed char-&gt;const char*、char*</td> 
   <td style="width:348px;"><span style="color:#f33b45;">先转为char，再隐式转换</span></td> 
  </tr> 
  <tr> 
   <td style="width:559px;">char、unsigned char、signed char-&gt;string</td> 
   <td style="width:348px;"><span style="color:#f33b45;">构造方法，push_back、insert等方法</span></td> 
  </tr> 
  <tr> 
   <td style="width:559px;">[signed/unsigned] [short/long] int-&gt;[signed/unsigned] char</td> 
   <td style="width:348px;"><span style="color:#f33b45;">+'0'&nbsp; 数值为0~9</span></td> 
  </tr> 
  <tr> 
   <td style="width:559px;">[signed/unsigned] [short/long] int-&gt;float/[long] double或[signed/unsigned] [short/long] int</td> 
   <td style="width:348px;">隐式转换</td> 
  </tr> 
  <tr> 
   <td style="width:559px;">float/[long] double -&gt; [signed/unsigned] [short/long] int</td> 
   <td style="width:348px;">显示转换，否则警告(例如，warning C4244: “初始化”: 从“float”转换到“short”，可能丢失数据)</td> 
  </tr> 
  <tr> 
   <td style="width:559px;">string-&gt;const char *</td> 
   <td style="width:348px;"><span style="color:#f33b45;">使用string的c_str()函数</span></td> 
  </tr> 
  <tr> 
   <td style="width:559px;">string-&gt;const char *-&gt;char*</td> 
   <td style="width:348px;"><span style="color:#f33b45;">先转const char *，再使用const_cast&lt;char*&gt;()转char*</span></td> 
  </tr> 
  <tr> 
   <td style="width:559px;">[const] char *-&gt;string</td> 
   <td style="width:348px;">隐式转换</td> 
  </tr> 
  <tr> 
   <td style="width:559px;">const char *-&gt;char*</td> 
   <td style="width:348px;"><span style="color:#f33b45;">使用const_cast&lt;char*&gt;()转char*</span></td> 
  </tr> 
  <tr> 
   <td style="width:559px;">[const] char *-&gt;char[]</td> 
   <td style="width:348px;"><span style="color:#f33b45;">使用strncpy_s()函数</span></td> 
  </tr> 
  <tr> 
   <td style="width:559px;">char* -&gt;const char*</td> 
   <td style="width:348px;">隐式转换</td> 
  </tr> 
 </tbody> 
</table>

注:\[\]表示可选，/表示或者

总结

内置类型隐式转换即可，可能丢失数据

涉及指针使用const\_cast，涉及string类使用方法push\_back、c\_str等

建议不要使用C风格的const char \*、char\[\]等，string不香吗？？？

>     string s("nkjsf");  
>     const char\* ch = s.c\_str();  
>     cout << ch << endl;  
>     s = "efefd";  
>     cout << ch << endl;

> nkjsf
> 
> efefd

ch没有变，但是两次输出不一样。各位学完C再学C++的，字符串这里学学string吧，真的很不错。

# 全部代码 #

测试了部分，运行单个函数即可。

/*
    Project:TypeConvert
    Date:    2020/09/06
    Author:  Frank Yu
    */
    #include<iostream>
    #include<string>
    #include<typeinfo>
    using namespace std;
    
    void display(string type,string method)
    {
    	cout <<"转为:"<<type<< ",使用方法:" << method << endl;
    }
    
    void char2other(char c)
    {
    	unsigned char uc = c;
    	display("unsigned char","隐式转换");
    	cout << "转换后:" << uc<<endl;
    	signed char sc = c;
    	display("signed char", "隐式转换");
    	cout << "转换后:" << sc << endl;
    	int i = c;
    	display("int", "隐式转换");
    	cout << "转换后:" << i << endl;
    	unsigned int ui = c;
    	display("unsigned int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	signed int si = c;
    	display("signed int", "隐式转换");
    	cout << "转换后:" << si << endl;
    	unsigned short int usi = c;
    	display("unsigned short int", "隐式转换");
    	cout << "转换后:" << usi << endl;
    	short int s_i = c;
    	display("short int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = c;
    	display("long int", "隐式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = c;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = c;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    	float f = c;
    	display("float", "隐式转换");
    	cout << "转换后:" << f << endl;
    	double d = c;
    	display("double", "隐式转换");
    	cout << "转换后:" << d << endl;
    	long double ld = c;
    	display("long double", "隐式转换");
    	cout << "转换后:" << ld << endl;
    	wchar_t wc = c;
    	display("wchar_t", "隐式转换");
    	cout << "转换后:" << wc << endl;
    	string s(1,c);
    	display("string", "构造方法string（size_t n,char c）");
    	cout << "转换后:" << s << endl;
    	string s1;
    	s1.push_back(c);
    	display("string", "push_back");
    	cout << "转换后:" << s1 << endl;
    	const char* cc = &c;
    	display("const char*", "隐式转换");
    	cout << "转换后:" << cc << endl;
    	char* c_c = &c;
    	display("char*", "隐式转换");
    	cout << "转换后:" << c_c << endl;
    }
    
    void unsignedchar2other(unsigned char c)
    {
    	char uc = c;
    	display("char", "隐式转换");
    	cout << "转换后:" << uc << endl;
    	signed char sc = c;
    	display("signed char", "隐式转换");
    	cout << "转换后:" << sc << endl;
    	int i = c;
    	display("int", "隐式转换");
    	cout << "转换后:" << i << endl;
    	unsigned int ui = c;
    	display("unsigned int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	signed int si = c;
    	display("signed int", "隐式转换");
    	cout << "转换后:" << si << endl;
    	unsigned short int usi = c;
    	display("unsigned short int", "隐式转换");
    	cout << "转换后:" << usi << endl;
    	short int s_i = c;
    	display("short int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = c;
    	display("long int", "隐式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = c;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = c;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    	float f = c;
    	display("float", "隐式转换");
    	cout << "转换后:" << f << endl;
    	double d = c;
    	display("double", "隐式转换");
    	cout << "转换后:" << d << endl;
    	long double ld = c;
    	display("long double", "隐式转换");
    	cout << "转换后:" << ld << endl;
    	wchar_t wc = c;
    	display("wchar_t", "隐式转换");
    	cout << "转换后:" << wc << endl;
    	string s(1, c);
    	display("string", "构造方法string（size_t n,char c）");
    	cout << "转换后:" << s << endl;
    	string s1;
    	s1.push_back(c);
    	display("string", "push_back");
    	cout << "转换后:" << s1 << endl;
    	//先转为了char，因为直接转不行(unsigned char *无法转为const char *)
    	char h = c;
    	const char* cc = &h;
    	display("const char*", "显示转换");
    	cout << "转换后:" << *cc << endl;
    	char* c_c = &h;
    	display("char*", "显示转换");
    	cout << "转换后:" << *c_c << endl;
    }
    
    void signedchar2other(signed char c)
    {
    	char uc = c;
    	display("char", "隐式转换");
    	bool b = uc == c;
    	cout << b;
    	if (uc == c)cout << b;
    	cout << "转换后:" << uc << endl;
    	unsigned char sc = c;
    	display("unsigned char", "隐式转换");
    	cout << "转换后:" << sc << endl;
    	int i = c;
    	display("int", "隐式转换");
    	cout << "转换后:" << i << endl;
    	unsigned int ui = c;
    	display("unsigned int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	signed int si = c;
    	display("signed int", "隐式转换");
    	cout << "转换后:" << si << endl;
    	unsigned short int usi = c;
    	display("unsigned short int", "隐式转换");
    	cout << "转换后:" << usi << endl;
    	short int s_i = c;
    	display("short int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = c;
    	display("long int", "隐式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = c;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = c;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    	float f = c;
    	display("float", "隐式转换");
    	cout << "转换后:" << f << endl;
    	double d = c;
    	display("double", "隐式转换");
    	cout << "转换后:" << d << endl;
    	long double ld = c;
    	display("long double", "隐式转换");
    	cout << "转换后:" << ld << endl;
    	wchar_t wc = c;
    	display("wchar_t", "隐式转换");
    	cout << "转换后:" << wc << endl;
    	string s(1, c);
    	display("string", "构造方法string（size_t n,char c）");
    	cout << "转换后:" << s << endl;
    	string s1;
    	s1.push_back(c);
    	display("string", "push_back");
    	cout << "转换后:" << s1 << endl;
    	//先转为了char，因为直接转不行(signed char *无法转为const char *)
    	char h = c;
    	const char* cc = &h;
    	display("const char*", "显示转换");
    	cout << "转换后:" << *cc << endl;
    	char* c_c = &h;
    	display("char*", "显示转换");
    	cout << "转换后:" << *c_c << endl;
    }
    
    void int2other(int i)
    {
    	char c = i+'0';
    	display("int", "+'0'");
    	cout << "转换后:" << c << endl;
    	unsigned char uc = i+'0';
    	display("unsigned char", "隐式转换");
    	cout << "转换后:" << uc << endl;
    	signed char sc = i + '0';
    	display("signed char", "隐式转换");
    	cout << "转换后:" << sc << endl;
    	unsigned int ui = i;
    	display("unsigned int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	signed int si = i;
    	display("signed int", "隐式转换");
    	cout << "转换后:" << si << endl;
    	unsigned short int usi = i;
    	display("unsigned short int", "隐式转换");
    	cout << "转换后:" << usi << endl;
    	short int s_i = i;
    	display("short int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = i;
    	display("long int", "隐式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = i;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = i;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    	float f = i;
    	display("float", "隐式转换");
    	cout << "转换后:" << f << endl;
    	double d = i;
    	display("double", "隐式转换");
    	cout << "转换后:" << d << endl;
    	long double ld = i;
    	display("long double", "隐式转换");
    	cout << "转换后:" << ld << endl;
    	wchar_t wc = i;
    	display("wchar_t", "隐式转换");
    	cout << "转换后:" << wc << endl;
    	string s(1, i+'0');
    	display("string", "构造方法string（size_t n,char c）");
    	cout << "转换后:" << s << endl;
    	string s1;
    	s1.push_back(i+'0');
    	display("string", "push_back");
    	cout << "转换后:" << s1 << endl;
    	const char* cc = &c;
    	display("const char*", "隐式转换");
    	cout << "转换后:" << *cc << endl;
    	char* c_c = &c;
    	display("char*", "隐式转换");
    	cout << "转换后:" << *c_c << endl;
    
    }
    
    void unsignedint2other(unsigned int i)
    {
    	char c = i + '0';
    	display("int", "+'0'");
    	cout << "转换后:" << c << endl;
    	unsigned char uc = i + '0';
    	display("unsigned char", "隐式转换");
    	cout << "转换后:" << uc << endl;
    	signed char sc = i + '0';
    	display("signed char", "隐式转换");
    	cout << "转换后:" << sc << endl;
    	int ui = i;
    	display("int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	signed int si = i;
    	display("signed int", "隐式转换");
    	cout << "转换后:" << si << endl;
    	unsigned short int usi = i;
    	display("unsigned short int", "隐式转换");
    	cout << "转换后:" << usi << endl;
    	short int s_i = i;
    	display("short int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = i;
    	display("long int", "隐式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = i;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = i;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    	float f = i;
    	display("float", "隐式转换");
    	cout << "转换后:" << f << endl;
    	double d = i;
    	display("double", "隐式转换");
    	cout << "转换后:" << d << endl;
    	long double ld = i;
    	display("long double", "隐式转换");
    	cout << "转换后:" << ld << endl;
    	wchar_t wc = i;
    	display("wchar_t", "隐式转换");
    	cout << "转换后:" << wc << endl;
    	string s(1, i + '0');
    	display("string", "构造方法string（size_t n,char c）");
    	cout << "转换后:" << s << endl;
    	string s1;
    	s1.push_back(i + '0');
    	display("string", "push_back");
    	cout << "转换后:" << s1 << endl;
    	const char* cc = &c;
    	display("const char*", "隐式转换");
    	cout << "转换后:" << *cc << endl;
    	char* c_c = &c;
    	display("char*", "隐式转换");
    	cout << "转换后:" << *c_c << endl;
    
    }
    
    void signedint2other(signed int i)
    {
    	char c = i + '0';
    	display("int", "+'0'");
    	cout << "转换后:" << c << endl;
    	unsigned char uc = i + '0';
    	display("unsigned char", "隐式转换");
    	cout << "转换后:" << uc << endl;
    	signed char sc = i + '0';
    	display("signed char", "隐式转换");
    	cout << "转换后:" << sc << endl;
    	int ui = i;
    	display("int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	unsigned int si = i;
    	display("unsigned int", "隐式转换");
    	cout << "转换后:" << si << endl;
    	unsigned short int usi = i;
    	display("unsigned short int", "隐式转换");
    	cout << "转换后:" << usi << endl;
    	short int s_i = i;
    	display("short int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = i;
    	display("long int", "隐式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = i;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = i;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    	float f = i;
    	display("float", "隐式转换");
    	cout << "转换后:" << f << endl;
    	double d = i;
    	display("double", "隐式转换");
    	cout << "转换后:" << d << endl;
    	long double ld = i;
    	display("long double", "隐式转换");
    	cout << "转换后:" << ld << endl;
    	wchar_t wc = i;
    	display("wchar_t", "隐式转换");
    	cout << "转换后:" << wc << endl;
    	string s(1, i + '0');
    	display("string", "构造方法string（size_t n,char c）");
    	cout << "转换后:" << s << endl;
    	string s1;
    	s1.push_back(i + '0');
    	display("string", "push_back");
    	cout << "转换后:" << s1 << endl;
    	const char* cc = &c;
    	display("const char*", "隐式转换");
    	cout << "转换后:" << *cc << endl;
    	char* c_c = &c;
    	display("char*", "隐式转换");
    	cout << "转换后:" << *c_c << endl;
    
    }
    
    void shortint2other(short int i)
    {
    	char c = i + '0';
    	display("int", "+'0'");
    	cout << "转换后:" << c << endl;
    	unsigned char uc = i + '0';
    	display("unsigned char", "隐式转换");
    	cout << "转换后:" << uc << endl;
    	signed char sc = i + '0';
    	display("signed char", "隐式转换");
    	cout << "转换后:" << sc << endl;
    	int ui = i;
    	display("int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	unsigned int si = i;
    	display("unsigned int", "隐式转换");
    	cout << "转换后:" << si << endl;
    	unsigned short int usi = i;
    	display("unsigned short int", "隐式转换");
    	cout << "转换后:" << usi << endl;
    	signed int s_i = i;
    	display("signed int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = i;
    	display("long int", "隐式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = i;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = i;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    	float f = i;
    	display("float", "隐式转换");
    	cout << "转换后:" << f << endl;
    	double d = i;
    	display("double", "隐式转换");
    	cout << "转换后:" << d << endl;
    	long double ld = i;
    	display("long double", "隐式转换");
    	cout << "转换后:" << ld << endl;
    	wchar_t wc = i;
    	display("wchar_t", "隐式转换");
    	cout << "转换后:" << wc << endl;
    	string s(1, i + '0');
    	display("string", "构造方法string（size_t n,char c）");
    	cout << "转换后:" << s << endl;
    	string s1;
    	s1.push_back(i + '0');
    	display("string", "push_back");
    	cout << "转换后:" << s1 << endl;
    	const char* cc = &c;
    	display("const char*", "隐式转换");
    	cout << "转换后:" << *cc << endl;
    	char* c_c = &c;
    	display("char*", "隐式转换");
    	cout << "转换后:" << *c_c << endl;
    
    }
    
    void unsignedshortint2other(unsigned short int i)
    {
    	char c = i + '0';
    	display("int", "+'0'");
    	cout << "转换后:" << c << endl;
    	unsigned char uc = i + '0';
    	display("unsigned char", "隐式转换");
    	cout << "转换后:" << uc << endl;
    	signed char sc = i + '0';
    	display("signed char", "隐式转换");
    	cout << "转换后:" << sc << endl;
    	int ui = i;
    	display("int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	unsigned int si = i;
    	display("unsigned int", "隐式转换");
    	cout << "转换后:" << si << endl;
    	short int usi = i;
    	display("short int", "隐式转换");
    	cout << "转换后:" << usi << endl;
    	signed int s_i = i;
    	display("signed int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = i;
    	display("long int", "隐式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = i;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = i;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    	float f = i;
    	display("float", "隐式转换");
    	cout << "转换后:" << f << endl;
    	double d = i;
    	display("double", "隐式转换");
    	cout << "转换后:" << d << endl;
    	long double ld = i;
    	display("long double", "隐式转换");
    	cout << "转换后:" << ld << endl;
    	wchar_t wc = i;
    	display("wchar_t", "隐式转换");
    	cout << "转换后:" << wc << endl;
    	string s(1, i + '0');
    	display("string", "构造方法string（size_t n,char c）");
    	cout << "转换后:" << s << endl;
    	string s1;
    	s1.push_back(i + '0');
    	display("string", "push_back");
    	cout << "转换后:" << s1 << endl;
    	const char* cc = &c;
    	display("const char*", "隐式转换");
    	cout << "转换后:" << *cc << endl;
    	char* c_c = &c;
    	display("char*", "隐式转换");
    	cout << "转换后:" << *c_c << endl;
    }
    
    void signedshortint2other(signed short int i)
    {
    	char c = i + '0';
    	display("int", "+'0'");
    	cout << "转换后:" << c << endl;
    	unsigned char uc = i + '0';
    	display("unsigned char", "隐式转换");
    	cout << "转换后:" << uc << endl;
    	signed char sc = i + '0';
    	display("signed char", "隐式转换");
    	cout << "转换后:" << sc << endl;
    	int ui = i;
    	display("int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	unsigned int si = i;
    	display("unsigned int", "隐式转换");
    	cout << "转换后:" << si << endl;
    	short int usi = i;
    	display("short int", "隐式转换");
    	cout << "转换后:" << usi << endl;
    	signed int s_i = i;
    	display("signed int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = i;
    	display("long int", "隐式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = i;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = i;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    	float f = i;
    	display("float", "隐式转换");
    	cout << "转换后:" << f << endl;
    	double d = i;
    	display("double", "隐式转换");
    	cout << "转换后:" << d << endl;
    	long double ld = i;
    	display("long double", "隐式转换");
    	cout << "转换后:" << ld << endl;
    	wchar_t wc = i;
    	display("wchar_t", "隐式转换");
    	cout << "转换后:" << wc << endl;
    	string s(1, i + '0');
    	display("string", "构造方法string（size_t n,char c）");
    	cout << "转换后:" << s << endl;
    	string s1;
    	s1.push_back(i + '0');
    	display("string", "push_back");
    	cout << "转换后:" << s1 << endl;
    	const char* cc = &c;
    	display("const char*", "隐式转换");
    	cout << "转换后:" << *cc << endl;
    	char* c_c = &c;
    	display("char*", "隐式转换");
    	cout << "转换后:" << *c_c << endl;
    }
    
    void float2int(float f)
    {
    	int i = f;
    	display("int", "隐式转换");
    	cout << "转换后:" << i << endl;
    	unsigned int ui = f;
    	display("unsigned int", "隐式转换");
    	cout << "转换后:" << ui << endl;
    	short int si = (short int)f;
    	display("short int", "显式转换");
    	cout << "转换后:" << si << endl;
    	signed int s_i = f;
    	display("signed int", "隐式转换");
    	cout << "转换后:" << s_i << endl;
    	long int li = (long int)f;
    	display("long int", "显式转换");
    	cout << "转换后:" << li << endl;
    	signed long int sli = f;
    	display("signed long int", "隐式转换");
    	cout << "转换后:" << sli << endl;
    	unsigned long int uli = f;
    	display("unsigned long int", "隐式转换");
    	cout << "转换后:" << uli << endl;
    }
    
    void string2other(string s)
    {
    	const char * cc; 
    	cc = s.c_str();
    	display("const char *", "使用方法c_str");
    	cout << "转换后:" << cc << endl;
    	char * c = const_cast<char*>(cc);
    	display("char *", "c_str转为const char *,再使用const_cast<char*>()转为char *");
    	cout << "转换后:" << c << endl;
    }
    
    void constchar2other(const char* cc)
    {
    	string s = cc;
    	display("string", "隐式转换");
    	cout << "转换后:" << s << endl;
    	char * c = const_cast<char*>(cc);
    	display("char *", "const_cast<char*>()");
    	cout << "转换后:" << c << endl;
    	char ca[10];
    	display("char[]", "strncpy_s()");
    	strncpy_s(ca, cc, 10);
    	cout << "转换后:" << ca << endl;
    }
    
    void char_2other(char* c)
    {
    	string s = c;
    	display("string", "隐式转换");
    	cout << "转换后:" << s << endl;
    	const char * cc = c;
    	display("const char *", "隐式转换");
    	cout << "转换后:" << cc << endl;
    	char ca[10];
    	display("char[]", "strncpy_s()");
    	strncpy_s(ca, c, 10);
    	cout << "转换后:" << ca << endl;
    }
    
    int main()
    {
    	//char2other('n');
    	unsignedchar2other('n');
    	//signedchar2other('n');
    	//signedchar2other('n');
    	//int2other(9);
    	//unsignedint2other(9);
    	//float2int(9.3);
    	//string2other("abcd");
    	//const char* cc = "abcd";
    	//constchar2other("abcd");
    	//char_2other("sdfesgrf");
    
    	//问题1  ch会变
    	//string s("nkjsf");
    	//const char* ch = s.c_str();
    	//cout << ch << endl;
    	//s = "efefd";
    	//cout << ch << endl;
    	//问题2  char2other函数输出cc没有烫 unsignedchar2other输出cc有烫
    	//char c = 'n';
    	//const char *cc = &c;
    	//cout << cc << endl;
    }

更多数据结构与算法实现：[数据结构（严蔚敏版）与算法的实现（含全部代码）][Link 1]

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[Link 1]: https://blog.csdn.net/lady_killer9/article/details/82695895