arduino string 用法摘选

arduino 截取 字符串 截取substring

String stringOne = "Content-Type: text/html";
  Serial.println(stringOne);

  // substring(index) looks for the substring from the index position to the end:
  if (stringOne.substring(19) == "html") {
    Serial.println("It's an html file");
  }
  // you can also look for a substring in the middle of a string:
  if (stringOne.substring(14, 18) == "text") {
    Serial.println("It's a text-based file");

字符串转成整型,string to int

String instring2="123e456y78a";
Serial.println(instring2.toInt());  //包含有英文,输出0
Serial.println(instring2.substring(2).toInt());//2
Serial.println(instring2.substring(0,3).toInt());//123
Serial.println(instring2.substring(4,7).toInt());//456

指定位置替换字符(char)

String reportString = "SensorReading: 456";
reportString.setCharAt(13, '=');//字符从0开始计算,左边开始计算
Serial.println(reportString);