public static string Join( string separator, params string[] value )
第一個參數separator是表示你要用什麼分隔符號，例如,。
第二個參數則是要合併的String Array
使用範例如下，輸出為1,2,3,4
String source="1234"; char[] charArray=source.ToCharArray(); String dist=String.Join(",",charArray); Console.WriteLine(dist);
// -------------------------------------- // i2c_scanner // // Version 1 // This program (or code that looks like it) // can be found in many places. // For example on the Arduino.cc forum. // The original author is not know. // Version 2, Juni 2012, Using Arduino 1.0.1 // Adapted to be as simple as possible by Arduino.cc user Krodal // Version 3, Feb 26 2013 // V3 by louarnold // Version 4, March 3, 2013, Using Arduino 1.0.3 // by Arduino.cc user Krodal. // Changes by louarnold removed. // Scanning addresses changed from 0...127 to 1...119, // according to the i2c scanner by Nick Gammon // http://www.gammon.com.au/forum/?id=10896 // Version 5, March 28, 2013 // As version 4, but address scans now to 127. // A sensor seems to use address 120. // Version 6, November 27, 2015. // Added waiting for the Leonardo serial communication. // // // This sketch tests the standard 7-bit addresses // Devices with higher bit address might not be seen properly. // #include <Wire.h> void setup() { Wire.begin(); Serial.begin(9600); while (!Serial); // Leonardo: wait for serial monitor Serial.println("\nI2C Scanner"); } void loop() { byte error, address; int nDevices; Serial.println("Scanning..."); nDevices = 0; for(address = 1; address < 127; address++ ) { // The i2c_scanner uses the return value of // the Write.endTransmisstion to see if // a device did acknowledge to the address. Wire.beginTransmission(address); error = Wire.endTransmission(); if (error == 0) { Serial.print("I2C device found at address 0x"); if (address<16) Serial.print("0"); Serial.print(address,HEX); Serial.println(" !"); nDevices++; } else if (error==4) { Serial.print("Unknown error at address 0x"); if (address<16) Serial.print("0"); Serial.println(address,HEX); } } if (nDevices == 0) Serial.println("No I2C devices found\n"); else Serial.println("done\n"); delay(5000); // wait 5 seconds for next scan }
unsigned long start=millis(); int delaytime=3000; void loop() { while (millis()<start+delaytime) { ; } sendData(); }
unsigned long start=millis(); unsigned long delay=3000; if (millis()-start>delay) { sendData(); start=millis(); }
unsigned long number=4294967295; void setup() { // put your setup code here, to run once: Serial.begin(9600); Serial.println("number is :"+String(number)); number+=1; Serial.println("number+1 is :"+String(number)); }
unsigned long number=4294967295; unsigned long testNumber=4294967295; void setup() { // put your setup code here, to run once: Serial.begin(9600); Serial.println("number is :"+String(number)); number+=1; Serial.println("number+1 is :"+String(number)); Serial.println("number- 2^32-1 :"+String(number-testNumber)); }
#include <SPI.h> #include <Ethernet.h> #include <PubSubClient.h> // Update these with values suitable for your network. byte mac[] = { 0xDE, 0xED, 0xBA, 0xFE, 0xFE, 0xED }; IPAddress ip(172, 16, 0, 100); IPAddress server(172, 16, 0, 2); void callback(char* topic, byte* payload, unsigned int length) { Serial.print("Message arrived ["); Serial.print(topic); Serial.print("] "); for (int i=0;i<length;i++) { Serial.print((char)payload[i]); } Serial.println(); } EthernetClient ethClient; PubSubClient client(ethClient); void reconnect() { // Loop until we're reconnected while (!client.connected()) { Serial.print("Attempting MQTT connection..."); // Attempt to connect if (client.connect("arduinoClient")) { Serial.println("connected"); // Once connected, publish an announcement... client.publish("outTopic","hello world"); // ... and resubscribe client.subscribe("inTopic"); } else { Serial.print("failed, rc="); Serial.print(client.state()); Serial.println(" try again in 5 seconds"); // Wait 5 seconds before retrying delay(5000); } } } void setup() { Serial.begin(57600); client.setServer(server, 1883); client.setCallback(callback); Ethernet.begin(mac, ip); // Allow the hardware to sort itself out delay(1500); } void loop() { if (!client.connected()) { reconnect(); } client.loop(); }
if (client.connect("arduinoClient"))
