Question 193150 in Javascript Question posted in
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Javascript – need validation to check multiple format

I am validating strings in multiple formats.

  • Any integer x (matched) if(x < 2)no matched.
  • Numbers with hyphens x-y if(y > x) matched, x-y-z (no matched)
  • Format – x;y;z;g (matched), x;x;z;z (no matched)*

Always value >= 2

I created a regexp ^d+((;d+)*|-d+)?$ but there are problems:

  • 2 format if(y < x) matched
  • 3 format x;z;z matched
Tags:

3

Answers


  1. 0

    You can split the string and process your parts individually:

    const valid = str => {

  const match = str.match(/^[d;]+$|^(d+)(-)(d+)$/);
  
  if(!match){
    return false;
  }
  
  const pos = 2; // position of '-' delimiter in the match
  if(match[pos] === '-'){
    return match[pos + 1] - match[pos - 1] > 0 && match[pos -1] >= 2;
  }

  const numbers = str.trim().split(/s*;s*/g);
  return numbers.every(num => num >=2) && new Set(numbers).size === numbers.length;
  
}
  

const strings = ["2;3;2", "5-4", "a;1", "2;301;44", "2", "2-3", "6-90", "2;3;4;5", "5;4", "2-3-5", "3;1"];

for(const str of strings){
  console.log(str, ':', valid(str));
}
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  2. 0

    Using regex only, you can not do math.

    You can update your pattern using 3 capture groups, and then handle the x-y scenario using parseInt and make sure that y > x

    For the x;y;z scenario you can split on ; and check if there are no duplicate values.

    ^([2-9]|[1-9]d+)(?:-([2-9]|[1-9]d+)|((?:;d+)+))?$

    The pattern matches:

    • ^ Start of string
    • ([2-9]|[1-9]d+) Capture group 1, match either a digit 2-9 or 10+
    • (?: Non capture group for the 2 alternatives:
      • -([2-9]|[1-9]d+) Capture group 2, match - followed by a digit 2-9 or 10+
      • | Or
      • ( Capture group 3
        • (?:;d+)+ Match 1+ repetitions of ; and 1+ digits
      • ) Close group 3
    • )? Close the non capture group and make it optional
    • $ End of string

    Regex demo

    const regex = /^([2-9]|[1-9]d+)(?:-([2-9]|[1-9]d+)|((?:;d+)+))?$/;
[
  "1", "1;1", "1-2", "3-2", "9-7", "9-8", "2", "2-1", "2-3", "5;4", "6-90", "3;2;1", "2;3;4;3", "6-90-1", "1;2;3", "2;3;4;1", "2;1;2", "2;3;4;9", "1;2;3;1", "2;301;44"
].forEach(s => {
  const m = s.match(regex);
  if (m) {
    const gr1 = parseInt(m[1]);
    if (undefined !== m[2] && parseInt(m[2]) > gr1)
      console.log(`Correct for ${s}`);
    if (undefined === m[2] && undefined === m[3])
      console.log(`Correct for ${s}`);
    if (undefined !== m[3]) {
      const parts = m[3].split(";").filter(Boolean).concat(m[1])
      if ((new Set(parts)).size === parts.length)
        console.log(`Correct for ${s}`);
    }
  }
})
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  3. 0

    To validate multiple formats using jQuery, you can utilize regular expressions (regex) to match the desired formats. Here’s an example of how you can implement this:

    <!DOCTYPE html>
<html>
<head>
  <title>Format Validation</title>
</head>
<body>
  <form id="form-example">
    <input type="text" id="myInput">
    <input type="submit" value="Submit">
  </form>
<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
  <script>
    $(document).ready(function() {
      $('#form-example').submit(function(event) {
        event.preventDefault(); // Prevent form submission

        // Get the input value
        var inputValue = $('#myInput').val();

        // Define the regex patterns for the allowed formats
        var emailRegex = /^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+.[A-Za-z]{2,}$/;
        var phoneRegex = /^d{10}$/;
        var dateRegex = /^d{2}/d{2}/d{4}$/;

        // Check if the input matches any of the defined formats
        if (emailRegex.test(inputValue)) {
          alert('Valid email format');
        } else if (phoneRegex.test(inputValue)) {
          alert('Valid phone number format');
        } else if (dateRegex.test(inputValue)) {
          alert('Valid date format');
        } else {
          alert('Invalid format');
        }
      });
    });
  </script>
</body>
</html>
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