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49 ****************************************************************************/
50
51 #include <QFile>
52 #include <QTextStream>
53
process_line(const QByteArray &)54 static void process_line(const QByteArray &)
55 {
56 }
57
process_line(const QString &)58 static void process_line(const QString &)
59 {
60 }
61
noStream_snippet()62 static void noStream_snippet()
63 {
64 //! [0]
65 QFile file("in.txt");
66 if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
67 return;
68
69 while (!file.atEnd()) {
70 QByteArray line = file.readLine();
71 process_line(line);
72 }
73 //! [0]
74 }
75
readTextStream_snippet()76 static void readTextStream_snippet()
77 {
78 //! [1]
79 QFile file("in.txt");
80 if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
81 return;
82
83 QTextStream in(&file);
84 while (!in.atEnd()) {
85 QString line = in.readLine();
86 process_line(line);
87 }
88 //! [1]
89 }
90
writeTextStream_snippet()91 static void writeTextStream_snippet()
92 {
93 //! [2]
94 QFile file("out.txt");
95 if (!file.open(QIODevice::WriteOnly | QIODevice::Text))
96 return;
97
98 QTextStream out(&file);
99 out << "The magic number is: " << 49 << "\n";
100 //! [2]
101 }
102
writeDataStream_snippet()103 static void writeDataStream_snippet()
104 {
105 QFile file("out.dat");
106 if (!file.open(QIODevice::WriteOnly))
107 return;
108
109 QDataStream out(&file);
110 out << "The magic number is: " << 49 << "\n";
111 }
112
readRegularEmptyFile_snippet()113 static void readRegularEmptyFile_snippet()
114 {
115 //! [3]
116 QFile file("/proc/modules");
117 if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
118 return;
119
120 QTextStream in(&file);
121 QString line = in.readLine();
122 while (!line.isNull()) {
123 process_line(line);
124 line = in.readLine();
125 }
126 //! [3]
127 }
128
main()129 int main()
130 {
131 lineByLine_snippet();
132 writeStream_snippet();
133 }
134