QByteArray：如何在其中搜索字符

Question

Starting from a QByteArray, I'd like to search "\\n" char inside my QByteArray and join all the characters from the beginning up to "\\n" and save them in a QString; after that, I'd pass to the following bytes up to the next "\\n" and save these into a new QString

QByteArray MyArray= (all data from my previous process);
quint16 ByteArrayCount = MyArray.count(); // number of bytes composing MyArray
quint16 mycounter;
QString myString;
while (mycounter < ByteArrayCount)
{
    if(MyArray[mycounter] != "\n")
      myString.append(MyArray[mycounter]);
    mycounter++;
}

This to append all bytes preceeding a new line; my problem is how to evaluate MyArray[counter], since I'm not able to check every byte when the counter increases.

Solution?

Answer 1

You could save yourself the trouble and simply:

QString s(myArray);
QStringList resultStrings = s.split('\n');

This will give you a list of strings split for every new line character, which is what you sound like you want to do.

Also, not to belabor the point, but you don't initialize your counter, and you really should ;)

Answer 2

Here is simple example of using function hello

QString str = "ooops\nhello mama\n daddy cool";
QByteArray bta;
bta.append(str);
for(quint16 index = bta.indexOf('\n'); 
            index != -1; 
            index = bta.indexOf('\n', index+1)) {
   /**
    * Do something with index
    **/
}

But according to your question there is not so clear when you say that you "not able to check every byte". If you know diapasons of available mem, you can use raw data with:

const char * ptr = MyArray.constData();

and use custom validators:

while(ptr){
    if(valid(ptr) && ptr == '\n') {
        /**
         * do something ...
         **/
    }
    ptr++;
}

ow and also in C/C++:

"\n" != 'n'

because "\\n" - is const C string(char[2]) containing \\n and EOF('\\0') and '\\n' - is just simple C char;