How does using stringstream to extract an integer value from a string differ from simply using explicit value casting to change the type?
Example:
string a = "1234";
int x;
x= int (a);
vs.
string a = "1234";
int x;
stringstream (a) >> x;
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Marcel
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5Well for one thing `x= int (a);` won't work. – Captain Obvlious Jan 08 '16 at 22:32
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My bad, I had mixed up the data types. – Marcel Jan 08 '16 at 22:33
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2@Marcel If you meant something different, you should change your question too... – deviantfan Jan 08 '16 at 22:37
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@Marcel deviantfan is right, the example code does not match your question and without an update it's just nonsense. – Captain Obvlious Jan 08 '16 at 22:48
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As you noted, the first example will not work. As I had managed to misunderstand an article, I was under the impression that one could change string types to integer types, which was of course incorrect. Therefore, the question is answered. – Marcel Jan 08 '16 at 23:21
1 Answers
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Well, major difference is that:
string a = "1234";
int x;
x= int (a);
does not compile, there is no conversion from std::string to int. Modern way to convert std::string to int is to use stoi function, but be carefull with it because it will throw for "x1234" but will hapilly parse: "1234x".
marcinj
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@Marcel its all in the link I provided, `...takes as many characters as possible to form a valid base-n (where n=base) integer number `, and throws std::invalid_argument `if no conversion could be performed`. – marcinj Jan 11 '16 at 10:57