const char * tag1[]={"abc","xyz"};
how to convert tag1 in std::string?
std::string tag2(tag1)
it simply copies tag1[0] to tag2. what i want is to convert the whole tag1 array into string.
Any ideas or workaround?
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cpplearner
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secretgenes
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5what do you want to achieve?? `string` is a string, not a list of strings. – Jean-François Fabre Nov 29 '16 at 09:51
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@Jean-FrançoisFabre : i simply want to convert the whole tag1 array into a single string. – secretgenes Nov 29 '16 at 09:53
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Take a look: http://stackoverflow.com/questions/5689003/how-to-implode-a-vector-of-strings-into-a-string-the-elegant-way NB: Arrays are evil. – Aneri Nov 29 '16 at 09:59
1 Answers
4
Since you want to merge array of C-strings into one std::string, you can do this:
std::string tag2;
for (auto ptr : tag1) {
tag2.append(ptr);
}
Iterate over C-strings array and append them to destination std::string.
Direct copy of tag1 array to pre-allocated std::string won't work because of null-terminators at end of each C-string in tag1. You will get abc\0xyz, instead of abcxyz
Starl1ght
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1probably calculating the total size and reserving is a bit more efficient without carpifying the code much – David Haim Nov 29 '16 at 09:58