JavaScript: Truncate a string up to a specified length

JavaScript fundamental (ES6 Syntax): Exercise-117 with Solution

Truncate String to Length

Write a JavaScript program to truncate a string up to a specified length.

Note: Determine if the string's length is greater than num. Return the string truncated to the desired length, with '...' appended to the end or the original string.

• Determine if String.prototype.length is greater than num.
• Return the string truncated to the desired length, with '...' appended to the end or the original string.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2

// Define the 'truncateString' function.
const truncateString = (str, num) =>
  // Check if the length of the string is greater than the specified number.
  str.length > num ? 
    // If so, truncate the string to the specified length and add ellipsis if necessary.
    str.slice(0, num > 3 ? num - 3 : num) + '...'
    // If not, return the original string.
    : str;

// Example usage: Truncate a string if it exceeds a certain length.
console.log(truncateString('boomerang', 7));
// Output: "boom..."

Output:

boom...

Visual Presentation:

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-117-1 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript program that truncates a string to a specified length and adds an ellipsis if it exceeds that length.
• Write a JavaScript function that shortens a string to a maximum number of characters, preserving whole words when possible.
• Write a JavaScript program that validates the string’s length and returns a truncated version if it is longer than the given limit.

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