Arduino SD - rewindDirectory()用法及代碼示例

file.rewindDirectory()

#include <SD.h>

File root;

void setup() {
  Serial.begin(9600);
  pinMode(10, OUTPUT);
  SD.begin(10);
  root = SD.open("/");
  printDirectory(root, 0);
  Serial.println();

  Serial.println("PRINT AGAIN");
  Serial.println("-----------");
  root.rewindDirectory();  // Return to the first file in the directory
  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
      break;
    }

    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);
    }
  }
}