Arduino receive data from software serial - json

Question

Sorry for my weak English. I'm trying to receive the json data from Sim800 on my Arduino. To read the data on the serial port I used the following code:
while(serialSIM800.available()==0); //Wait until the data is received
String content = "";
while(serialSIM800.available()>0){ // When data is received
content = content + char(char (serialSIM800.read()));
}
Serial.print(content);
But incomplete data is received. As follows:
{"id":"1212","temp":"24","hum","4
For the better result I used the following code:
byte x;
char data[128];
void sim800Reply() {
x=0;
do{
while(serialSIM800.available()==0);
data[x]=serialSIM800.read();
Serial.print(data[x]);
x++;
} while(!(data[x-1]=='K'&&data[x-2]=='O'));
}
Data is completely received. As follows:
{"id":"1212","temp":"24","hum","45","date":"11.2018","status":"200"}
OK
But I think this code is not good and there are problems.for example If the serialSIM800 is not available like when sim800 are not connected, The following code causes crash while(serialSIM800.available()==0); Because this is always true OR If there is an error and OK Was not received, The following code causes crash while(!(data[x-1]=='K'&&data[x-2]=='O')); Because this is always true.The maximum data length is 120 bytes, What should I do to Receive the Json data from Arduino serial? Thank you all.

Answer 1

for start try:
if (serialSIM800.available()) {
String content = serialSIM800.readString();
Serial.print(content);
}
in setup() add serialSIM800.setTimeut(50);

Answer 2

Finally, I changed the code as follows:
String dump(bool printData) {
byte while_cunt = 0;
while (serialSIM800.available() == 0){
while_cunt++;
delay(15); // It can change for a proper delay
if(while_cunt >=250){ // If the data from serial was not received past 3.75 seconds
Serial.println("return");
return ""; // Exit from dump function
}
}
String content = "";
while (serialSIM800.available() > 0) {
content += serialSIM800.readString();
}
if (printData) {
Serial.println(content);
}
return content;
}
It can return and print serial data And it works fast Because every 15 milliseconds checks that the data has been received and if it has not been received for a certain period of time(In this case 3.75 seconds), it will be out of process and will not crash.
Examples for this function:
serialSIM800.println("AT");
dump(true);
// print Received response from sim800
serialSIM800.println("AT");
String str = dump(true);
// print Received response from sim800 and Saved in variable named 'str'
serialSIM800.println("AT");
String str = dump(false);
//Save response in variable named 'str' without print