QString 转 const char *
QString str = "abc";
const char *ch1 = array.toLatin1().data();
qDebug() << ch1; // "abc"
const char *ch2 = str.toStdString().c_str();
qDebug() << ch2; // "abc"
const char * 转 QString
const char *ch = "hello world !";
QString str1 = QString::fromLocal8Bit(ch);
qDebug() << str1; // "hello world !"
QString str2(ch);
qDebug() << str2; // "hello world !"
const unsigned char * 转 QString
const unsigned char str[5] = {'t', 'e', 's', 't'};
string s = (char *)str;
qDebug() << QString::fromStdString(s);
QString 转 int
bool ok;
QString str1 = "0xf8";
int value1 = str1.toInt(&ok, 16);
qDebug() << ok << " " << value1; // true 248
QString str2 = "012";
int value2 = str2.toInt(&ok, 10);
qDebug() << ok << " " << value2; // true 12
QString str3 = "a";
int value3 = str3.toInt(&ok, 10);
qDebug() << ok << " " << value3; // false 0
int 转 QString
int a = 5;
qDebug() << QString::number(a, 10); // "5"
double b = 1.2;
QString str;
str.setNum(b);
qDebug() << str; // "1.2"
QString 转 ASCII码
QString str = "abcde";
QByteArray array = str.toLatin1();
for (int i = 0; i < array.size(); ++i)
qDebug() << (int)array.at(i); // 97 98 99 100 101
ASCII码 转 QString
QByteArray array;
array.append(97);
array.append(102);
array.append(108);
array.append(116);
for (int i = 0; i < array.size(); ++i)
qDebug() << QChar(array.at(i)); // 'a' 'f' 'l' 't'