Arduino Reference - FileOpenNextFile

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SD : File class

## openNextFile()

Reports the next file or folder in a directory.

#### Syntax

file.openNextFile()

#### Parameters

file: an instance of the File class that is a directory

#### Returns

char : the next file or folder in the path

#### Example

#include <SD.h>
File root;
void setup()
{
Serial.begin(9600);
pinMode(10, OUTPUT);
SD.begin(10);
root = SD.open("/");
printDirectory(root, 0);
Serial.println("done!");
}
void loop()
{
// nothing happens after setup finishes.
}
void printDirectory(File dir, int numTabs) {
while(true) {
File entry = dir.openNextFile();
if (! entry) {
// no more files
Serial.println("**nomorefiles**");
}
for (uint8_t i=0; i<numTabs; i++) {
Serial.print('\t');
}
Serial.print(entry.name());
if (entry.isDirectory()) {
Serial.println("/");
printDirectory(entry, numTabs+1);
} else {
// files have sizes, directories do not
Serial.print("\t\t");
Serial.println(entry.size(), DEC);
}
}
}
[Get Code]

#### See Also

- isDirectory()
- rewindDirectory()

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