GUI is a human-computer interaction interface, and QT is one of the tools of GUI.
For the processing of serial port data or other transmitted data.
The Arduino library has many pre packaged and user-friendly libraries, and the string library is one of them.
1. Obtain the nth character parameter of the string (index index).
2. String before concatenation; The string parameters (str1, str2) with no return value are concatenated well in str1.
3. Check if the strings are equal. Parameters (str1, str2) return a value of bool type.
4. Find a specific character or string in the string and use the function parameter (string1, val, from) 1. String 2. Specific character or string 3. Index index success. Return position failure. Return -1.
5. Measure the string length parameter (string) and return the value of string length.
6. Truncate a certain position of the string, parameter (string from to). The original string to be truncated should be indexed from the first word to the next word, and the index should return the string.
7 string to int parameter (string) returns an integer value.
8. Automatically clear the front and back blank data.