Convert arduino String to C language String
To convert an Arduino String
to a C language string, you can use the c_str()
function provided by the Arduino String
class. The c_str()
function returns a pointer to a null-terminated character array that represents the contents of the String
object.
Here are the steps to convert an Arduino String
to a C language string:
- Declare a variable of type
String
in Arduino and initialize it with the desired value. - Use the
c_str()
function on theString
object to obtain a pointer to the character array representation of theString
. - Assign the pointer obtained from
c_str()
to a variable of typechar*
in C.
Here's an example code snippet that demonstrates the conversion:
#include <Arduino.h>
void setup() {
String arduinoString = "Hello, World!"; // Step 1: Declare and initialize a String object
const char* cString = arduinoString.c_str(); // Step 2: Convert the String to a C string
// Use the cString variable as a C string
// ...
}
void loop() {
// ...
}
In the example above, arduinoString
is an Arduino String
object that is initialized with the value "Hello, World!". The c_str()
function is then used to obtain a pointer (cString
) to the C-style string representation of arduinoString
.
You can now use the cString
variable as a C string in your code, for example, by passing it to functions that expect a const char*
parameter.
Note that the C-style string obtained using c_str()
is read-only, so you should not modify its contents directly. If you need to modify the string, you should create a new character array and copy the contents of the String
object into it using functions like strcpy()
or memcpy()
.