How to force a value to be converted to int type in javascript

JavaScript is a weakly typed language, which means that the types of variables and expressions are determined dynamically and can be changed as needed at runtime. Due to this property, JavaScript has some very convenient properties, such as rapid development and simple syntax, but also has some weaknesses, such as the possibility of unexpected behavior due to type errors.

To help avoid these potential problems in JavaScript, developers can use type casting. This includes converting any values ​​to a specific type, such as int or string, to ensure they have the corresponding type. This article will focus on converting values ​​to type int.

1. What is int?

int, or integer, is a whole number in mathematics or computer science that has no decimal or fractional part. In JavaScript, there is no real int type - all numbers are stored in floating point memory. This means that the number must be converted to a floating point number before any calculations can be performed. However, in some cases we may need to explicitly convert a number to an integer type.

2. Convert string to integer in JavaScript

1. parseInt(string, radix) function

parseInt function parses a string into a number Built-in function, which returns an integer. You can use this to convert a string to type int.

This function requires two parameters: the first parameter is a string; the second parameter is the base value (that is, the base value of the number to be parsed), which is an optional value, and the default parameter is 10. The base value can be 2, 8, 10, 16, etc. If a radix value is used, the parsed result will be expressed in that radix.

Use the parseInt function to convert a string to an integer in the following way:

let str = '123';
let num = parseInt(str);

console.log(num); // 123

The above example demonstrates how to convert the string '123' to an integer. The parseInt function takes the string '123' and converts it to the number 123.

You can use the following method to convert a binary string to a decimal integer:

let str = '1010';
let num = parseInt(str, 2);

console.log(num); // 10

2. Number() function

   Number() function can also convert characters Converts a string to a number, but it returns a floating point number. This means it can handle arbitrary numeric values, not just integers. When converting a string to an integer, you can use the Number() function, but you need to use Math.floor() to round down.

The following are methods to convert strings to integers:

let str = '123';
let num = Math.floor(Number(str));

console.log(num); // 123

3. Convert other values ​​to integers in JavaScript

In addition to converting strings In addition, JavaScript can also convert other values ​​​​to integers, such as:

1. Convert a Boolean value to an integer

let bool = true;
let num = bool ? 1 : 0;

console.log(num); // 1

In this example, the Boolean value true is converted to Integer 1, converts the Boolean value false to the integer 0.

2. Convert a floating point number to an integer

let float = 3.14159;
let integer = Math.floor(float);

console.log(integer); // 3

In this example, use the Math.floor() function to convert the floating point number 3.14159 to the integer 3.

4. Summary

In JavaScript, type casting is a useful technique to ensure that variables have the correct type, thereby avoiding potential problems. This article describes methods for converting values ​​to type int, including using the parseInt() function, the Number() function, and the Math.floor() function. Although there is no real int type in JavaScript, developers can use these methods to convert numbers to integer types to avoid type errors and other potential problems.

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