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Javascript if statement is executing on false condition

const resultsDiv = document.getElementById('results');
const value = '2555-555-5555';
const regex = /(1s?)?(d{3}|(d{3}))[-s]?d{3}[-s]?d{4}/; //I found this is an incorrect regex

if (regex.test(value)) {
  console.log(regex.test(value)); //is false
  resultsDiv.querySelector("p").textContent = `Valid US number: ${value}`;
} else {
  resultsDiv.querySelector("p").textContent = `Invalid US number: ${value}`;
}
<div id="results"><p></p></div>

The if condition here should not be executing.

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2

Answers


  1. 0

    i have looked to your example, modify some things statically and the result is fine

    const value = "123465789";
const regex = /(1s?)?(d{3}|(d{3}))[-s]?d{3}[-s]?d{4}/g;

if (!value) {
    alert("Please provide a phone number");
}

if (regex.test(value)) {
    console.log(regex.test(value));
    console.log("if")
} else {
    console.log("else")
    console.log(regex.test(value))
}

    the result is :
    else
    false

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  2. 0

    Can you try like this

    Valid

    const value = "(555) 555-1234";
const regex = /(1s?)?(d{3}|(d{3}))[-s]?d{3}[-s]?d{4}/g;

if (!value) {
  alert("Please provide a phone number");
}

if (value.match(regex)) {
  console.log(value.match(regex));
  console.log(`Valid US number: ${value}`);
} else {
  console.log(`Invalid US number: ${value}`);
}

    Console: [‘(555) 555-1234’]

    Valid US number: (555) 555-1234

    Invalid Phone

    const value = "99999";
const regex = /(1s?)?(d{3}|(d{3}))[-s]?d{3}[-s]?d{4}/g;

if (!value) {
  alert("Please provide a phone number");
}

if (value.match(regex)) {
  console.log(value.match(regex));
  console.log(`Valid US number: ${value}`);
} else {
  console.log(`Invalid US number: ${value}`);
}

    Invalid US number: 99999

    Use match https://www.w3schools.com/jsref/jsref_match.asp

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