未知类型名称字符串 C++
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/29692326/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Unknown type name string C++
提问by Jimmy
I'm new to C++ and have had some help with my program to compare two XML files. This is the code I have:
我是 C++ 的新手，并且在我的程序中得到了一些帮助来比较两个 XML 文件。这是我的代码：
#include "pugixml.hpp"
#include <iostream>
#include <unordered_map>
int main() {
pugi::xml_document doca, docb;
std::map<string, pugi::xml_node> mapa, mapb;
if (!doca.load_file("a.xml") || !docb.load_file("b.xml"))
return 1;
for (auto& node: doca.child("site_entries").children("entry")) {
const char* id = node.child_value("id");
mapa[new std::string(id, strlen(id))] = node;
}
for (auto& node: docb.child("site_entries").children("entry"))
const char* idcs = node.child_value("id");
std::string id = new std::string(idcs, strlen(idcs));
if (!mapa.erase(id)) {
mapb[id] = node;
}
}
}
I seem to get a lot of errors when I try and compile it.
当我尝试编译它时，我似乎遇到了很多错误。
The first one I get is this:
我得到的第一个是这样的：
src/main.cpp:10:14: error: unknown type name 'string'; did you mean 'std::string'?
std::map<string, pugi::xml_node> mapa, mapb;
~~~~~^~~
From what I understand, I have specified it correctly. Should I change it as it requests or is something else a-miss?
据我了解，我已经正确指定了它。我应该按照它的要求更改它还是有其他问题？
回答by shauryachats
You need to include the string library in order to use std::string.
您需要包含字符串库才能使用std::string.
Since you mentioned a lot of errors, I suspect you forgot to include <cstring>in order to use strlen().
既然你提到了很多错误，我怀疑你忘记包含<cstring>为了使用strlen().
#include <string>
#include <cstring>
回答by moffeltje
You have to include the string library:
您必须包含字符串库：
#include <string>
回答by Masudur Rahman
Use the following way:
使用以下方式：
std::string varName = "var value";
std::string varName = "var value";
I'm using Clion IDE and it worked for me.
我正在使用 Clion IDE，它对我有用。
