get-string
wayland/esp32-preferences/get-string
Retrieve specified string from currently open namespace. If record doesn't exist, the String pin will output "NA".
get-string
@/get-string
Retrieve specified string from currently open namespace. If record doesn't exist, the String pin will output "NA".
Prefs@/preferences
A preferences object.
Keystring
Key name. Limited to 15 chars.
Sizenumber
Maximum size of string (number of bytes). Must be a constant value. Any changes during program execution will be ignored.
UPDpulse
Update
Donepulse
Pulse on read.
Stringstring
String retrieved from storage (or "NA" if key doesn't exist).
C++ implementation
#pragma XOD evaluate_on_pin disable
#pragma XOD evaluate_on_pin enable input_UPD
node {
CStringView view;
char* cString;
size_t cap;
void evaluate(Context ctx) {
if (isSettingUp()) {
cap = getValue<input_Size>(ctx) + 1;
cString = new char[cap];
view = CStringView(cString);
}
if (isInputDirty<input_UPD>(ctx)) {
auto prefs = getValue<input_Prefs>(ctx);
auto xStringKey = getValue<input_Key>(ctx);
int N=length(xStringKey);
if (N>15 || N<1) {
raiseError(ctx);
return;
}
N +=1;
char cStringKey[N];
for(int i=0;i<N;i++)
cStringKey[i]=0;
dump(xStringKey, cStringKey);
String str = prefs -> getString(cStringKey, "NA");
int strLen = str.length() + 1;
str.toCharArray(cString, strLen);
emitValue<output_String>(ctx, XString(&view));
emitValue<output_Done>(ctx, 1);
}
}
}