How do I chop/slice/trim off last character in string using Javascript?

slice vs substring: Before you slice, a thin slice of theory

While slice is generally preferred for its readability and convenience, you can use substring as an alternative. Let's compare them:

let str = "Surprise!";
let slicedStr = str.slice(0, -1); // "Surpris" without its exclamation surprise
let substringStr = str.substring(0, str.length - 1); // Also gives "Surpris"
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The key point here is that in both cases, you are left with a new string and your original string remains the same. slice has the upper hand as it simplifies code by making you unfettered by the string's length, which is especially useful with dynamic or variable length strings.

It's not just last character!

There might be times when you need to remove more than just the last character. Here's how you could achieve that with slice:

let str = "Cut here ->";
let newStr = str.slice(0, -3); // "Cut here", because the '->' has been sliced off!
console.log(newStr);
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And sometimes, you might want to remove based on a specific pattern, for that, you can use the mighty sword of regular expressions:

let str = "image_grayscale.png";
let newName = str.replace(/_grayscale$/, ""); // "image.png" after removing the dark shade
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Avant-garde slicing: Be precise with your cuts

Moreover, you can mix and match slicing with other methods like lastIndexOf for even more control:

let str = "find_the_gold";
let position = str.lastIndexOf("_"); // Making sure the gold is there
if (position !== -1) {
    str = str.slice(0, position); // "find_the" - found the gold!
}
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Dealing with numeric strings

When dealing with numeric strings, you might consider parseFloat and toFixed:

let numStr = "12345.00";
let formattedNum = parseFloat(numStr).toFixed(1); // Gives you "12345.0"
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Remember, toFixed rounds off the number. To remove the last digit without rounding, again, slice is your go-to tool:

let numStr = "12345.00";
let trimmedNumStr = numStr.slice(0, -1); // "12345.0" - no rounding, just slicing!
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