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标题: 学习中遇到问题了，哪位老师来给点拨一下吧 [打印本页]

作者: 四香油饼 时间: 25-11-2009 11:57
标题: 学习中遇到问题了，哪位老师来给点拨一下吧
在学习c++基础知识，做习题：），希望能早日写出3000行的代码，可是上来就遇到问题搞不懂了，还请大家给我指点一下：
题目：Create a Text class that contains a string object to hold
the text of a file. Give it two constructors: a default
constructor and a constructor that takes a string
argument that is the name of the file to open. When the
second constructor is used, open the file and read the
contents into the string member object. Add a member
function contents( ) to return the string so (for example)
it can be printed. In main( ), open a file using Text and
print the contents

我的代码如下：
text.h:
#ifndef TEXT_H
#define TEXT_H
#include <string>
class Text
{
public:
std::string Contents(void);
Text();
Text(char *st);
~Text();
private:
std::string File_Content;
}
#endif

text.cpp:
#include "text.h"
#include <iostream>
#include <fstream>
using namespace std;

Text::Text()
{}

Text::Text(char *st)
{
string line;
ifstream In_File(*st);
while (getline(In_File,line))
{
File_Content = File_Content + line + endl;
}
}

Text::~Text()
{}

string Text::Contents(void)
{
return (File_Content);
}

e1.cpp:
#include "text.h"
#include <iostream>
using namespace std;

int main(int argc, char* argv[])
{
Text file1("text.h");
cout << file1.Contents() << endl;
}

我现在遇到的问题是，一编译，就出现一些奇怪的错误：
g++ -c -o e1.o e1.cpp
In file included from C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/
c++/3.4.5/bits/localefwd.h:48,
               from C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/
c++/3.4.5/ios:48,
               from C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/
c++/3.4.5/ostream:45,
               from C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/
c++/3.4.5/iostream:45,
               from e1.cpp:2:
C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/c++/3.4.5/bits/functex
cept.h:36: error: expected unqualified-id before "namespace"
e1.cpp:10: error: expected declaration before '}' token
make: *** [e1.o] Error 1

我大概知道是namespace出了问题，可是搞不太明白是哪里出了问题，我改了一下text.h，改成下面的样子，
// text.h
#ifndef TEXT_H
#define TEXT_H
#include <string>
class Text
{
using namespace std;
public:
string Contents(void);
Text();
Text(char *st);
~Text();
private:
string File_Content;
}
#endif

错误信息变成了这样，我实在是晕了，老师给指点一下吧

g++ -c -o e1.o e1.cpp
In file included from e1.cpp:1:
text.h:7: error: expected nested-name-specifier before "namespace"
text.h:7: error: expected unqualified-id before "namespace"
text.h:7: error: expected `;' before "namespace"
text.h:7: error: expected unqualified-id before "namespace"
text.h:9: error: `string' does not name a type
text.h:14: error: `string' does not name a type
In file included from C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/
c++/3.4.5/bits/localefwd.h:48,
               from C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/
c++/3.4.5/ios:48,
               from C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/
c++/3.4.5/ostream:45,
               from C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/
c++/3.4.5/iostream:45,
               from e1.cpp:2:
C:/MinGW/bin/../lib/gcc/mingw32/3.4.5/../../../../include/c++/3.4.5/bits/functex
cept.h:36: error: expected unqualified-id before "namespace"
e1.cpp: In function `int main(int, char**)':
e1.cpp:8: error: 'class Text' has no member named 'Contents'
e1.cpp: At global scope:
e1.cpp:10: error: expected declaration before '}' token

作者: coredump 时间: 25-11-2009 12:02
class 声明，最后要有个分号

class XXX {
。。。
};

作者: 四香油饼 时间: 25-11-2009 13:20

原帖由 coredump 于 25-11-2009 12:02 发表

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class 声明，最后要有个分号

class XXX {
。。。
};

竟然如此简单！
加上个分号，两种方法都能通过了！（程序还有别的小毛病，那些都好找了）

这个事情说明：我程序写得太少了

作者: yuba 时间: 25-11-2009 13:31

原帖由 四香油饼 于 25-11-2009 13:20 发表

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这个事情说明：我程序写得太少了

这个事情说明：编译器太不友好了

作者: 一半 时间: 25-11-2009 15:46
饼叔真是刻苦！

作者: MillerYang 时间: 25-11-2009 15:59
主席辛苦了。。。

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