I am looking for a way to get a String between 2 Strings using Arduino. This is the source String:
Hello, my name is John Doe# and my favourite number is 32#.
The output has to be:
String name = "John Doe"; //Between "name is " and "#"
String favouriteNumber = "32"; //Between "number is " and "#"
How can this be achieved with Arduino?
I am not able to find any information online about this. Those examples for C are not working anyway. I understand that using String is not recommended in Arduino, but I have to do it this way to make things simpler.
By the way, this method of using a '#' to indicate the end of the data is not an ideal way to do it as I would like the input to be more human readable and more natural. Would anyone please suggest another way to do this as well?
Thanks in advance!
Function midString find the substring that is between two other strings "start" and "finish". If such a string does not exist, it returns "". A test code is included too.
void setup() {
test();
}
void loop() {
delay(100);
}
String midString(String str, String start, String finish){
int locStart = str.indexOf(start);
if (locStart==-1) return "";
locStart += start.length();
int locFinish = str.indexOf(finish, locStart);
if (locFinish==-1) return "";
return str.substring(locStart, locFinish);
}
void test(){
Serial.begin(115200);
String str = "Get a substring of a String. The starting index is inclusive (the corresponding character is included in the substring), but the optional ending index is exclusive";
Serial.print(">");
Serial.print( midString( str, "substring", "String" ) );
Serial.println("<");
Serial.print(">");
Serial.print( midString( str, "substring", "." ) );
Serial.println("<");
Serial.print(">");
Serial.print( midString( str, "corresponding", "inclusive" ) );
Serial.println("<");
Serial.print(">");
Serial.print( midString( str, "object", "inclusive" ) );
Serial.println("<");
}
just searched for this and saw no answer so i cooked one up.
i prefer working with String as well because of code readability and simplicity.
for me its more important than squeezing every last drop of juice out of my arduino.
String name = GetStringBetweenStrings("Hello, my name is John Doe# and my favourite number is 32#." ,"name is ","#");
String GetStringBetweenStrings(String input, String firstdel, String enddel){
int posfrom = input.indexOf(firstdel) + firstdel.length();
int posto = input.indexOf(enddel);
return input.substring(posfrom, posto);
}
watch out for the first case its fine, but for the second one you would have to change the second filter sting to "#." so it doesn't use the first occurrence of the #
Related
So I have a question where I am checking if a string has every letter of the alphabet in it. I was able to check if there is alphabet in the string, but I'm not sure how to check if there is EVERY alphabet in said string. Here's the code
fun isPangram (pangram: Array<String>) : String {
var panString : String
var outcome = ""
for (i in pangram.indices){
panString = pangram[i]
if (panString.matches(".^*[a-z].*".toRegex())){
outcome = outcome.plus('1')
}
else {outcome = outcome.plus('0')}
}
return outcome
}
Any ideas are welcomed Thanks.
I think it would be easier to check if all members of the alphabet range are in each string than to use Regex:
fun isPangram(pangram: Array<String>): String =
pangram.joinToString("") { inputString ->
when {
('a'..'z').all { it in inputString.lowercase() } -> "1"
else -> "0"
}
}
Hi this is how you can make with regular expression
Kotlin Syntax
fun isStrinfContainsAllAlphabeta( input: String) {
return input.lowercase()
.replace("[^a-z]".toRegex(), "")
.replace("(.)(?=.*\\1)".toRegex(), "")
.length == 26;
}
In java:
public static boolean isStrinfContainsAllAlphabeta(String input) {
return input.toLowerCase()
.replace("[^a-z]", "")
.replace("(.)(?=.*\\1)", "")
.length() == 26;
}
the function takes only one string. The first "replaceAll" removes all the non-alphabet characters, The second one removes the duplicated character, then you check how many characters remained.
Just to bounce off Tenfour04's solution, if you write two functions (one for the pangram check, one for processing the array) I feel like you can make it a little more readable, since they're really two separate tasks. (This is partly an excuse to show you some Kotlin tricks!)
val String.isPangram get() = ('a'..'z').all { this.contains(it, ignoreCase = true) }
fun checkPangrams(strings: Array<String>) =
strings.joinToString("") { if (it.isPangram) "1" else "0" }
You could use an extension function instead of an extension property (so it.isPangram()), or just a plain function with a parameter (isPangram(it)), but you can write stuff that almost reads like English, if you want!
I have a string coming from PC through serial to a microcontroller (Arduino), e.g.:
"HDD: 55 - CPU: 12.6 - Weather: Cloudy [...] $";
by this function I found:
String inputStringPC = "";
boolean stringCompletePC = false;
void serialEvent() {
while (Serial.available()) {
char inChar = (char)Serial.read();
inputStringPC += inChar;
if (inChar == '$') // end marker of the string
{
stringCompletePC = true;
}
}
}
I would like to extract the first number of it after the word HDD, CPU and also get the string after Weather (ie "cloudy"); my thinking is something like that:
int HDD = <function that does that>(Keyword HDD);
double CPU = <function that does that>(Keyword CPU);
char Weather[] = <function that does that>(Keyword Weather);
What is the right function to do that?
I looked into inputStringSerial.indexOf("HDD") but I am still a learner to properly understand what it does and don't know if theres a better function.
My approach yielded some syntax errors and confused me with the difference in usage between "String inputStringSerial" (class?) and "char inputStringSerial[]" (variable?). When I do 'string inputStringSerial = "";' PlatformIO complains that "string" is undefined. Any help to understand its usage here is greatly appreciated.
Thanks a bunch.
The String class provides member functions to search and copy the contents of the String. That class and all its member functions are documented in the Arduino Reference:
https://www.arduino.cc/reference/tr/language/variables/data-types/stringobject/
The other way a list of characters can be represented is a char array, confusingly also called a string or cstring. The functions to search and copy the contents of a char array are documented at
http://www.cplusplus.com/reference/cstring/
Here is a simple Sketch that copies and prints the value of the Weather field using a String object. Use this same pattern - with different head and terminator values - to copy the string values of the other fields.
Once you have the string values of HDD and CPU, you'll need to call functions to convert those string values into int and float values. See the String member functions toInt() and toFloat() at
https://www.arduino.cc/reference/en/language/variables/data-types/string/functions/toint/
or the char array functions atoi() and atof() at
http://www.cplusplus.com/reference/cstdlib/atoi/?kw=atoi
String inputStringPC = "HDD: 55 - CPU: 12.6 - Weather: Cloudy [...] $";
const char headWeather[] = "Weather: "; // the prefix of the weather value
const char dashTerminator[] = " -"; // one possible suffix of a value
const char dollarTerminator[] = " $"; // the other possible suffix of a value
void setup() {
int firstIndex; // index into inputStringPC of the first char of the value
int lastIndex; // index just past the last character of the value
Serial.begin(9600);
// find the Weather field and copy its string value.
// Use similar code to copy the values of the other fields.
// NOTE: This code contains no error checking for unexpected input values.
firstIndex = inputStringPC.indexOf(headWeather);
firstIndex += strlen(headWeather); // firstIndex is now the index of the char just past the head.
lastIndex = inputStringPC.indexOf(dollarTerminator, firstIndex);
String value = inputStringPC.substring(firstIndex, lastIndex);
Serial.print("Weather value = '");
Serial.print(value);
Serial.println("'");
}
void loop() {
// put your main code here, to run repeatedly:
}
When run on an Arduio Uno, this Sketch produces:
Weather value = 'Cloudy [...]'
I need to remove last char in string in my case it's comma (","):
foreach(line; fcontent.splitLines)
{
string row = line.split.map!(a=>format("'%s', ", a)).join;
writeln(row.chop.chop);
}
I have found only one way - to call chop two times. First remove \r\n and second remove last char.
Is there any better ways?
import std.array;
if (!row.empty)
row.popBack();
As it usually happens with string processing, it depends on how much Unicode do you care about.
If you only work with ASCII it is very simple:
import std.encoding;
// no "nice" ASCII literals, D really encourages Unicode
auto str1 = cast(AsciiString) "abcde";
str1 = str1[0 .. $-1]; // get slice of everything but last byte
auto str2 = cast(AsciiString) "abcde\n\r";
str2 = str2[0 .. $-3]; // same principle
In "last char" actually means unicode code point (http://unicode.org/glossary/#code_point) it gets a bit more complicated. Easy way is to just rely on D automatic decoding and algorithms:
import std.range, std.stdio;
auto range = "кириллица".retro.drop(1).retro();
writeln(range);
Here retro (http://dlang.org/phobos/std_range.html#.retro) is a lazy reverse iteration function. It takes any range (unicode string is a valid range) and returns wrapper that is capable of iterating it backwards.
drop (http://dlang.org/phobos/std_range.html#.drop) simply pops a single range element and ignores it. Calling retro again will reverse the iteration order back to normal, but now with the last element dropped.
Reason why it is different from ASCII version is because of nature of Unicode (specifically UTF-8 which D defaults to) - it does not allow random access to any code point. You actually need to decode them all one by one to get to any desired index. Fortunately, D takes care of all decoding for you hiding it behind convenient range interface.
For those who want even more Unicode correctness, it should be possible to operate on graphemes (http://unicode.org/glossary/#grapheme):
import std.range, std.uni, std.stdio;
auto range = "abcde".byGrapheme.retro.drop(1).retro();
writeln(range);
Sadly, looks like this specific pattern is not curently supported because of bug in Phobos. I have created an issue about it : https://issues.dlang.org/show_bug.cgi?id=14394
NOTE: Updated my answer to be a bit cleaner and removed the lambda function in 'map!' as it was a little ugly.
import std.algorithm, std.stdio;
import std.string;
void main(){
string fcontent = "I am a test\nFile\nwith some,\nCommas here and\nthere,\n";
auto data = fcontent
.splitLines
.map!(a => a.replaceLast(","))
.join("\n");
writefln("%s", data);
}
auto replaceLast(string line, string toReplace){
auto o = line.lastIndexOf(toReplace);
return o >= 0 ? line[0..o] : line;
}
module main;
import std.stdio : writeln;
import std.string : lineSplitter, join;
import std.algorithm : map, splitter, each;
enum fcontent = "some text\r\nnext line\r\n";
void main()
{
fcontent.lineSplitter.map!(a=>a.splitter(' ')
.map!(b=>"'" ~ b ~ "'")
.join(", "))
.each!writeln;
}
Take a look, I use this extension method to replace any last character or sub-string, for example:
string testStr = "Happy holiday!";<br>
Console.Write(testStr.ReplaceVeryLast("holiday!", "Easter!"));
public static class StringExtensions
{
public static string ReplaceVeryLast(this string sStr, string sSearch, string sReplace = "")
{
int pos = 0;
sStr = sStr.Trim();
do
{
pos = sStr.LastIndexOf(sSearch, StringComparison.CurrentCultureIgnoreCase);
if (pos >= 0 && pos + sSearch.Length == sStr.Length)
sStr = sStr.Substring(0, pos) + sReplace;
} while (pos == (sStr.Length - sSearch.Length + 1));
return sStr;
}
}
Could somebody explain what is wrong with this code. WHY is the if statement always false when it is matching the exact strings..I have tried it with == as well..Still, every time I am getting No Match Found !!.
String inData = "";
char inChar;
String property;
String a = "test";
void loop() {
Serial.println("String Comparison");
if(Serial.available() > 0){
while(Serial.available()>0) {
inChar = Serial.read();
inData.concat(inChar);
}
//Extracting Property
property = inData.substring(inData.lastIndexOf(":")+2); // Extracts the String "test"
Serial.println("Property:" +property);
if(property.equals(a)){ // It never matches though, it is TRUE all the time
Serial.println(" Matched !! ");
}
else
Serial.println(" Match Not Found !! ");
inData = "";
}
delay(5000);
}
Since I am able to see matches match and misses miss I think I need more information to replicate the error.
Since I don't see it happening I would guess it has to do with whatever the input is and how this line parses it.
property = inData.substring(inData.lastIndexOf(":")+2); // Extracts the String "test"
What is the current input that is failing?
Can you include your printed output with that input?
Add a line to print out property.length() to test for hidden whitespace characters
I want to limit the no. of character that can be put on JTextField because on my database I have this column that has Sex,Status (which the no. of char. allowed is 1 only).
and Middle Initial (which the no. of char. allowed is 2 only).
This what I have in my mind :
(for Sex,Status column)
String text = jTextField2.getText();
int count = text.();
if (count>1) {
(delete the next character that will be input)
}
(for M.I. column)
String text = jTextField1.getText();
int count = text.();
if (count>2) {
(delete the next character that will be input)
}
is this possible? is there a command that will delete the next character, so the no. of char. is acceptable for my database?
Sure. Just use String#substring.
String middleInitial = "JKL";
middleInitial.substring(0, 2);
System.out.println(middleInitial); // => JK
Similarly, you can use substring(0, 1) for sex.
It might be better if sex is an enum, though.
public enum Sex {
MALE("m"), FEMALE("f");
final String symbol;
private Sex(String symbol) {
this.symbol = symbol;
}
}
Now you can use it like this:
String sex = "male";
Sex.valueOf(sex.toUpperCase());
Or directly
Sex.MALE;
Instead of a text field for sex, you might use a JComboBox so the user can only choose one of the two options. This way you're sure to have valid input.