JavaScript: Check a given value contains alpha, dash and underscore

JavaScript validation with regular expression: Exercise-20 with Solution

Alpha-Dash-Underscore Check

Write a JavaScript function to check if a given value contains alpha, a dash and an underscore.

Visual Presentation:

Sample Solution:

JavaScript Code:

function is_alphaDash(str)
{
 regexp = /^[a-z0-9_\-]+$/i;
  
        if (regexp.test(str))
          {
            return true;
          }
        else
          {
            return false;
          }
}

console.log(is_alphaDash('12-133'));

console.log(is_alphaDash('100_23'));

Output:

true
true

Flowchart:

Live Demo:

See the Pen javascript-regexp-exercise-20 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that checks if a string contains only alphabetic characters, dashes, and underscores using a regular expression.
• Write a JavaScript function that validates the input and returns true if it matches the alpha-dash-underscore pattern exactly.
• Write a JavaScript function that removes spaces from a string before testing it against an alpha-dash-underscore regex.
• Write a JavaScript function that tests multiple strings for compliance with alpha, dash, and underscore rules.

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