C++ - Получение строки текста внутри символа и текста

Question

Я создаю консольную программу, которая получит строку текста, которая начинается с определенного символа. Я работаю с .txt-файл в качестве ввода текста, и это он:

<?xml version="1.0" encoding="utf-8"?> 
<vector android:height="64.0dip" android:width="64.0dip" android:viewportWidth="24.0" android:viewportHeight="24.0" 
    xmlns:android="http://schemas.android.com/apk/res/android"> 
    <path android:fillColor="#00000000" android:pathData="M12.05,7.7c-1.1,0,-2,0.94,-2,2.05v0.5h4v-0.5C14.05,8.65,13.15,7.7,12.05,7.7z" /> 
    <path android:fillColor="@*common:color/qs_toggles_color" android:pathData="M15.05,10.25l0.0,-0.5c0.0,-1.66 -1.34,-3.0 -3.0,-3.0s-2.99,1.34 -2.99,3.0l-0.01,0.5c-0.55,0.0 -1.0,0.45 -1.0,1.0l0.0,5.0c0.0,0.55 0.45,1.0 1.0,1.0l6.0,0.0c0.55,0.0 1.0,-0.45 1.0,-1.0l0.0,-5.0C16.05,10.7 15.6,10.25 15.05,10.25zM12.05,14.75c-0.55,0.0 -1.0,-0.45 -1.0,-1.0c0.0,-0.55 0.45,-1.0 1.0,-1.0s1.0,0.45 1.0,1.0C13.05,14.3 12.6,14.75 12.05,14.75zM14.05,10.25l-4.0,0.0l0.0,-0.5c0.0,-1.1 0.9,-2.05 2.0,-2.05s2.0,0.94 2.0,2.05L14.05,10.25z" /> 
    <path android:fillColor="@*common:color/qs_toggles_color" android:pathData="M16.5,2.5c3.3,1.5 5.6,4.7 6.0,8.5L24.0,11.0C23.4,4.8 18.3,0.0 12.0,0.0c-0.2,0.0 -0.4,0.0 -0.7,0.0l3.8,3.8L16.5,2.5zM7.5,21.5c-3.3,-1.5 -5.6,-4.7 -6.0,-8.5L0.1,13.0C0.6,19.2 5.7,24.0 12.0,24.0c0.2,0.0 0.4,0.0 0.7,0.0l-3.8,-3.8L7.5,21.5z" /> 
</vector> 

То, что я хочу сделать, это извлечь

M12.05,7.7c-1.1,0,-2,0.94,-2,2.05v0.5h4v-0.5C14.05,8.65,13.15,7.7,12.05,7.7z 

и:

M15.05,10.25l0.0,-0.5c0.0,-1.66 -1.34,-3.0 -3.0,-3.0s-2.99,1.34 -2.99,3.0l-0.01,0.5c-0.55,0.0 -1.0,0.45 -1.0,1.0l0.0,5.0c0.0,0.55 0.45,1.0 1.0,1.0l6.0,0.0c0.55,0.0 1.0,-0.45 1.0,-1.0l0.0,-5.0C16.05,10.7 15.6,10.25 15.05,10.25zM12.05,14.75c-0.55,0.0 -1.0,-0.45 -1.0,-1.0c0.0,-0.55 0.45,-1.0 1.0,-1.0s1.0,0.45 1.0,1.0C13.05,14.3 12.6,14.75 12.05,14.75zM14.05,10.25l-4.0,0.0l0.0,-0.5c0.0,-1.1 0.9,-2.05 2.0,-2.05s2.0,0.94 2.0,2.05L14.05,10.25z 

и:

M16.5,2.5c3.3,1.5 5.6,4.7 6.0,8.5L24.0,11.0C23.4,4.8 18.3,0.0 12.0,0.0c-0.2,0.0 -0.4,0.0 -0.7,0.0l3.8,3.8L16.5,2.5zM7.5,21.5c-3.3,-1.5 -5.6,-4.7 -6.0,-8.5L0.1,13.0C0.6,19.2 5.7,24.0 12.0,24.0c0.2,0.0 0.4,0.0 0.7,0.0l-3.8,-3.8L7.5,21.5z 

и положить их в свои строки. Я пытался сделать это путем удаления всего текста до этих строк, и после того, как, но я получаю Необработанное исключение, с этим кодом:

int main(int argc, const char * argv[]) 
{ 
    string str = "<?xml versim on=\"1.0\" encoding=\"utf-8\"?> <vector android:height=\"64.0dip\" android:width=\"64.0dip\" android:viewportWidth=\"24.0\" android:viewportHeight=\"24.0\" xmlns:android=\"http://schemas.android.com/apk/res/android\"> <path android:fillColor=\"#00000000\" android:pathData=\"M12.05,7.7c-1.1,0,-2,0.94,-2,2.05v0.5h4v-0.5C14.05,8.65,13.15,7.7,12.05,7.7z\" /> <path android:fillColor=\"@*common:color/qs_toggles_color\" android:pathData=\"M15.05,10.25l0.0,-0.5c0.0,-1.66 -1.34,-3.0 -3.0,-3.0s-2.99,1.34 -2.99,3.0l-0.01,0.5c-0.55,0.0 -1.0,0.45 -1.0,1.0l0.0,5.0c0.0,0.55 0.45,1.0 1.0,1.0l6.0,0.0c0.55,0.0 1.0,-0.45 1.0,-1.0l0.0,-5.0C16.05,10.7 15.6,10.25 15.05,10.25zM12.05,14.75c-0.55,0.0 -1.0,-0.45 -1.0,-1.0c0.0,-0.55 0.45,-1.0 1.0,-1.0s1.0,0.45 1.0,1.0C13.05,14.3 12.6,14.75 12.05,14.75zM14.05,10.25l-4.0,0.0l0.0,-0.5c0.0,-1.1 0.9,-2.05 2.0,-2.05s2.0,0.94 2.0,2.05L14.05,10.25z\" <path android:fillColor=\"@*common:color/qs_toggles_color\" android:pathData=\"M16.5,2.5c3.3,1.5 5.6,4.7 6.0,8.5L24.0,11.0C23.4,4.8 18.3,0.0 12.0,0.0c-0.2,0.0 -0.4,0.0 -0.7,0.0l3.8,3.8L16.5,2.5zM7.5,21.5c-3.3,-1.5 -5.6,-4.7 -6.0,-8.5L0.1,13.0C0.6,19.2 5.7,24.0 12.0,24.0c0.2,0.0 0.4,0.0 0.7,0.0l-3.8,-3.8L7.5,21.5z\" /> </vector>"; 
    string dp1= str; 
    dp1.replace(dp1.find("<?xml version=\"1.0\" encoding=\"utf-8\"?> <vector android:height=\"64.0dip\" android:width=\"64.0dip\" android:viewportWidth=\"24.0\" android:viewportHeight=\"24.0\" xmlns:android=\"http://schemas.android.com/apk/res/android\"> <path android:fillColor=\"#00000000\" android:pathData=\""), 269, ""); 
    dp1.replace(dp1.find("/> <path android:fillColor=\"@*common:color/qs_toggles_color\" android:pathData=\"M15.05,10.25l0.0,-0.5c0.0,-1.66 -1.34,-3.0 -3.0,-3.0s-2.99,1.34 -2.99,3.0l-0.01,0.5c-0.55,0.0 -1.0,0.45 -1.0,1.0l0.0,5.0c0.0,0.55 0.45,1.0 1.0,1.0l6.0,0.0c0.55,0.0 1.0,-0.45 1.0,-1.0l0.0,-5.0C16.05,10.7 15.6,10.25 15.05,10.25zM12.05,14.75c-0.55,0.0 -1.0,-0.45 -1.0,-1.0c0.0,-0.55 0.45,-1.0 1.0,-1.0s1.0,0.45 1.0,1.0C13.05,14.3 12.6,14.75 12.05,14.75zM14.05,10.25l-4.0,0.0l0.0,-0.5c0.0,-1.1 0.9,-2.05 2.0,-2.05s2.0,0.94 2.0,2.05L14.05,10.25z/> <path android:fillColor=\"@*common:color/qs_toggles_color\" android:pathData=\"M15.05,10.25l0.0,-0.5c0.0,-1.66 -1.34,-3.0 -3.0,-3.0s-2.99,1.34 -2.99,3.0l-0.01,0.5c-0.55,0.0 -1.0,0.45 -1.0,1.0l0.0,5.0c0.0,0.55 0.45,1.0 1.0,1.0l6.0,0.0c0.55,0.0 1.0,-0.45 1.0,-1.0l0.0,-5.0C16.05,10.7 15.6,10.25 15.05,10.25zM12.05,14.75c-0.55,0.0 -1.0,-0.45 -1.0,-1.0c0.0,-0.55 0.45,-1.0 1.0,-1.0s1.0,0.45 1.0,1.0C13.05,14.3 12.6,14.75 12.05,14.75zM14.05,10.25l-4.0,0.0l0.0,-0.5c0.0,-1.1 0.9,-2.05 2.0,-2.05s2.0,0.94 2.0,2.05L14.05,10.25z\" <path android:fillColor=\"@*common:color/qs_toggles_color\" android:pathData=\"M16.5,2.5c3.3,1.5 5.6,4.7 6.0,8.5L24.0,11.0C23.4,4.8 18.3,0.0 12.0,0.0c-0.2,0.0 -0.4,0.0 -0.7,0.0l3.8,3.8L16.5,2.5zM7.5,21.5c-3.3,-1.5 -5.6,-4.7 -6.0,-8.5L0.1,13.0C0.6,19.2 5.7,24.0 12.0,24.0c0.2,0.0 0.4,0.0 0.7,0.0l-3.8,-3.8L7.5,21.5z\" /> </vector>\""), 525, ""); 

    std::cout << dp1 << endl; 

    system ("PAUSE"); 
    return 0; 
} 

Так в основном, я хочу, чтобы извлечь эти 3 строки, указанной выше в свои собственные струны. Я думал, что могу извлечь их на основе их стартового символа, который является M. Спасибо

Answer 1

Хорошим способом извлечь данные из файла XML будет использование синтаксического анализа XML. Если ваш XML-файл изменился, у вас возникнут проблемы с ручным поиском строк, которые вы пытаетесь выполнить.

What XML parser should I use in C++?