How Can I Force JavaScript to Add Numbers Instead of Concatenating Strings?

Forcing JavaScript to Perform Mathematical Operations Instead of String Concatenation

When using JavaScript to manipulate numbers, unexpected behavior can occur if a number is inadvertently treated as a string. Consider the following example:

var dots = document.getElementById("txt").value; // 5
function increase() {
    dots = dots + 5;
}

The intention is to add 5 to the value of dots, which is an integer. However, JavaScript treats dots as a string, resulting in "5" (the original value) being concatenated with 5, producing "55" instead of the expected 10.

To resolve this issue and force JavaScript to perform mathematical operations on the value of dots, it's necessary to convert it to an integer using parseInt() before adding 5.

dots = parseInt(document.getElementById("txt").value, 10);

Here, parseInt() takes two arguments: the string representing the numeric value (the contents of the "txt" element) and a radix (base). In this case, we specify 10 to indicate that the number is in decimal (base-10) format.

By using parseInt(), you ensure that the value of dots is interpreted as an integer, enabling JavaScript to perform mathematical calculations correctly.

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