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43 lines
1.1 KiB
Plaintext
43 lines
1.1 KiB
Plaintext
/*
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String length()
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Examples of how to use length() in a String.
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Open the Serial Monitor and start sending characters to see the results.
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created 1 Aug 2010
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by Tom Igoe
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http://arduino.cc/en/Tutorial/StringLengthTrim
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This example code is in the public domain.
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*/
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String txtMsg = ""; // a string for incoming text
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int lastStringLength = txtMsg.length(); // previous length of the String
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void setup() {
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// open the serial port:
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Serial.begin(9600);
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}
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void loop() {
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// add any incoming characters to the String:
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while (Serial.available() > 0) {
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char inChar = Serial.read();
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txtMsg += inChar;
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}
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// print the message and a notice if it's changed:
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if (txtMsg.length() != lastStringLength) {
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Serial.println(txtMsg);
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Serial.println(txtMsg.length());
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// if the String's longer than 140 characters, complain:
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if (txtMsg.length() < 140) {
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Serial.println("That's a perfectly acceptable text message");
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}
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else {
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Serial.println("That's too long for a text message.");
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}
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// note the length for next time through the loop:
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lastStringLength = txtMsg.length();
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}
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} |