CODEWITHSUNDEEP
sqlitereact-native
Italo Rodrigo
Italo Rodrigo

Reputation: 1785

How do to log a Error Callback in SQLite?

I am trying to connect to a database using the code below:

import SQLite from 'react-native-sqlite-storage'

var db = SQLite.openDatabase({name : "banco.db", createFromLocation : 1}, this.successCB(), this.errorCB());

errorCB() {
  this.setState({message: "I NEED SHOW THE ERROR HERE"});
} 

successCB() {
  this.setState({message: "SQL executed fine"});
}

How to show the error on the errorCB function?

Upvotes: 0

Views: 1709

Answers (2)

Prasun
Prasun

Reputation: 5023

I used to open SQLite using following statement

database = SQLite.openDatabase({name: 'my.db', location: 'default'}, (db) => {
     db.transaction( tx => {
     tx.executeSql(`CREATE TABLE IF NOT EXISTS tableName (columnNames)`);
        }, error => {
           this.setState({message: error});
     });
 }, error => {
    this.setState({message: error});
});

Hope this will help!

Upvotes: 1

Michael Cheng
Michael Cheng

Reputation: 10461

This is in the documentation example. The error callback will get passed an argument containing the error. You are also not providing the correct value to openDatabase. You should be passing in functions, not trying to call the function.

Copy pasting the relevant parts from the documentation with comments to explain:

// Your error callback function that should take an argument that will contain your error.
errorCB(err) {
  console.log("SQL Error: " + err);
  // Here you can use err in your setState call.
}

openCB() {
  console.log("Database OPENED");
}

// openDatabase should be passed in the functions; openCB and errorCB in this example.
var db = SQLite.openDatabase("test.db", "1.0", "Test Database", 200000, openCB, errorCB);

// What you're doing is incorrect as it's akin to doing this which is wrong.
// var db = SQLite.openDatabase("test.db", "1.0", "Test Database", 200000, openCB(), errorCB());

This is really more of a basic JavaScript question where you need to be able to read the documentation and understand how to use a given API. If you're having trouble with this, I suggest reading up about Higher-Order Functions as it's fundamental to JavaScript.

Edit: To be very direct and answer the comments; this is what your code should look like:

import SQLite from 'react-native-sqlite-storage'

var db = SQLite.openDatabase({name : "banco.db", createFromLocation : 1}, this.successCB, this.errorCB);

// Making the assumption that these are in a class,
// otherwise add the const keyword before them.
// Convert these to arrow functions instead
// so they can more easily be passed as variables.
errorCB = (err) => {
  this.setState({message: err});
}

successCB = () => {
  this.setState({message: "SQL executed fine"});
}

Given your comments, I'll be very direct here. If you don't understand how functions, Higher-Order Functions, and variables/values work in JavaScript, you are going to have a very difficult time with React Native. Especially so if you are unfamiliar with ES6 syntax. Go through the book in that link or one of the many other great resources for learning the fundamentals of JavaScript before tackling React Native.

Upvotes: 1

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