How to Convert Int to Double in Flutter?

Learn how to convert integer int to double data types in Flutter, a crucial skill for handling numerical calculations and data manipulation in your apps.

Here we are going to use 6 different ways to convert integer values to double data types with examples and explanations.

6 Ways to Convert Int to Double in Flutter

In Flutter and Dart, there are several ways to convert an int value to a double value. Here are the main methods:

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1. Using the toDouble() method

This is the most straightforward way to convert an int to a double.

int myInt = 42;
double myDouble = myInt.toDouble(); // myDouble = 42.0

2. Using the double.parse() method with toString()

Here, we first convert the int to a String using toString(), and then use double.parse() to convert the String to a double.

int myInt = 42;
double myDouble = double.parse(myInt.toString()); // myDouble = 42.0

3. Using the double.parse() method with toStringAsFixed()

This method allows you to specify the number of decimal places when converting the int to a String before parsing it to a double.

int myInt = 42;
double myDouble = double.parse(myInt.toStringAsFixed(2)); // myDouble = 42.0

4. Using the double.fromInt() constructor

This is a more direct way to convert an int to a double using the double.fromInt() constructor.

int myInt = 42;
double myDouble = double.fromInt(myInt); // myDouble = 42.0

5. Using arithmetic operations

You can also perform arithmetic operations like addition or multiplication with 0.0 to convert an int to a double.

int myInt = 42;
double myDouble = myInt.toDouble() + 0.0; // myDouble = 42.0

6. Using the double() constructor

This method uses the double() constructor to convert the int value to a double.

int myInt = 42;
double myDouble = double(myInt); // myDouble = 42.0

Why do we need to Convert Int to double in dart

If you need to perform arithmetic operations that involve both integers and floating-point numbers, you may need to convert one type to the other to ensure compatibility and accuracy in calculations.

Numeric Operations

For example, if you’re dividing two integers and you want a floating-point result, you would need to convert one of the integers to a double before performing the division.

int intValue = 10;
double doubleValue = 3.0;
double result = intValue.toDouble() / doubleValue;

API Compatibility

In certain situations, APIs or libraries you’re working with might expect or return double values, even if the underlying data is inherently integer-based.

In such cases, you’d need to convert between the types to ensure proper communication and data handling.

int intValue = 5;
double doubleValue = intValue.toDouble();
// Pass doubleValue to an API or library that expects a double

Type Compatibility

Sometimes, you might need to ensure that a function or method parameter accepts a double rather than an integer.

In such cases, you would need to explicitly convert the integer to a double to match the required type.

void processDouble(double value) {
    // Do something with the double value
}

int intValue = 5;
processDouble(intValue.toDouble());

Display Requirements

Sometimes, you might need to display an integer value in a format that includes decimal places.

For example, if you’re displaying currency values or measurements, you may want to show them with decimal precision.

int intValue = 1000;
double doubleValue = intValue.toDouble();
String formattedValue = doubleValue.toStringAsFixed(2); // Display with two decimal places

At the End

Finally, you can easily change or convert data types from integer to double in flutter using the above examples. You can easily choose any one coding style according to your preferences and requirements.

Follow the official documentation to set up Flutter: Flutter Installation Guide.