[GH-ISSUE #228] no known conversion for argument 2 from 'char ()[20]' to 'char' #189

New issue

Closed

opened 2026-02-28 01:23:55 +03:00 by kerem · 0 comments

kerem commented

2026-02-28 01:23:55 +03:00

Owner

Originally created by @ovi1337 on GitHub (Sep 29, 2016).
Original GitHub issue: https://github.com/tzapu/WiFiManager/issues/228

Hi i'm using Platformio and would like to use your library for an ESP8266, but i can't use addParameter for strings, because i will get this error:

src/main.cpp:15:56: error: no matching function for call to 'ConfigManager::addParameter(const char [5], char (*)[20], int)'

Here is the whole error log of the compiling:

src/main.cpp:15:56: note: candidates are:
In file included from src/main.cpp:1:0:
lib/ConfigManager/ConfigManager.h:107:10: note: template<class T> void ConfigManager::addParameter(const char*, T*)
void addParameter(const char *name, T *variable) {
^
lib/ConfigManager/ConfigManager.h:107:10: note:   template argument deduction/substitution failed:
src/main.cpp:15:56: note:   candidate expects 2 arguments, 3 provided
configManager.addParameter("name", &config.name, 20);
^
In file included from src/main.cpp:1:0:

lib/ConfigManager/ConfigManager.h:110:10: note: void ConfigManager::addParameter(const char*, char*, size_t)
void addParameter(const char *name, char *variable, size_t size) {
^
lib/ConfigManager/ConfigManager.h:110:10: note:   no known conversion for argument 2 from 'char (*)[20]' to 'char*'
*** [.pioenvs/nodemcuv2/src/main.o] Error 1

If i'm commenting out the line configManager.addParameter("name", &config.name, 20); can i compile and use your library without any problems. But then i can't use strings/chars :(

Here is my main.cpp

#include "ConfigManager.h"

struct Config {
    char name[20];
    bool enabled;
    int8 hour;
} config;

ConfigManager configManager;

void setup() {
    // Setup config manager
    configManager.setAPName("Demo");
    configManager.setAPFilename("/index.html");
    configManager.addParameter("name", &config.name, 20);
    configManager.addParameter("enabled", &config.enabled);
    configManager.addParameter("hour", &config.hour);
    configManager.begin(config);

    //
}

void loop() {
    configManager.loop();
}

Can you help find out the problem and/or are you be able to help me for this problem?

Originally created by @ovi1337 on GitHub (Sep 29, 2016). Original GitHub issue: https://github.com/tzapu/WiFiManager/issues/228 Hi i'm using Platformio and would like to use your library for an ESP8266, but i can't use addParameter for strings, because i will get this error: ``` src/main.cpp:15:56: error: no matching function for call to 'ConfigManager::addParameter(const char [5], char (*)[20], int)' ``` Here is the whole error log of the compiling: ``` src/main.cpp:15:56: note: candidates are: In file included from src/main.cpp:1:0: lib/ConfigManager/ConfigManager.h:107:10: note: template<class T> void ConfigManager::addParameter(const char*, T*) void addParameter(const char *name, T *variable) { ^ lib/ConfigManager/ConfigManager.h:107:10: note: template argument deduction/substitution failed: src/main.cpp:15:56: note: candidate expects 2 arguments, 3 provided configManager.addParameter("name", &config.name, 20); ^ In file included from src/main.cpp:1:0: lib/ConfigManager/ConfigManager.h:110:10: note: void ConfigManager::addParameter(const char*, char*, size_t) void addParameter(const char *name, char *variable, size_t size) { ^ lib/ConfigManager/ConfigManager.h:110:10: note: no known conversion for argument 2 from 'char (*)[20]' to 'char*' *** [.pioenvs/nodemcuv2/src/main.o] Error 1 ``` If i'm commenting out the line `configManager.addParameter("name", &config.name, 20);` can i compile and use your library without any problems. But then i can't use strings/chars :( Here is my **main.cpp** ``` #include "ConfigManager.h" struct Config { char name[20]; bool enabled; int8 hour; } config; ConfigManager configManager; void setup() { // Setup config manager configManager.setAPName("Demo"); configManager.setAPFilename("/index.html"); configManager.addParameter("name", &config.name, 20); configManager.addParameter("enabled", &config.enabled); configManager.addParameter("hour", &config.hour); configManager.begin(config); // } void loop() { configManager.loop(); } ``` Can you help find out the problem and/or are you be able to help me for this problem?