How to cast a string to an integer in Dart

A string can be cast to an integer using the int.parse() method in Dart. The method takes a string as an argument and converts it into an integer.

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Code

The following code snippet demonstrates the usage of the int.parse method:

import 'dart:convert';
void main() {
    var a = 10; // An integer
    var b = "20"; // A string
    var c = int.parse(b);
    print(a + c);
}

The method also accepts strings that start with 0x0x; i.e., the format for hexadecimal numbers. Consider the code below which converts a hexadecimal string into an integer:​

import 'dart:convert';



void main() {

    var a = "0x1E"; // Hexadecimal value for 30

    var b = int.parse(a);

    print(b);

}

The method will throw a FormatException if the input is invalid. The method won’t accept characters that are not radix-10 or hexadecimal (e.g., “abc”).

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