请求将PHP正则表达式转换为适配jQuery验证的JavaScript代码

Let's walk through adapting your Contact Form 7 PHP regex into a working jQuery Validation method step by step.

First, complete the reusable "regex" validation method you started. We just need to add the regex test and a small cleanup step for user input:

$.validator.addMethod("regex", function(value, element, regexp) {
    var re = new RegExp(regexp);
    // Trim whitespace to handle accidental leading/trailing spaces
    return this.optional(element) || re.test(value.trim());
});

Next, apply this method to validate Danish phone numbers using your adapted regex. Since JavaScript regex syntax matches PHP's PCRE almost exactly, we can use the pattern directly as a regex literal (cleaner than a string with escaped backslashes):

// Initialize validation on your form
$("#your-contact-form-id").validate({
    rules: {
        // Replace "phone" with your actual field name (e.g., "tel")
        phone: {
            regex: /^((\(?\+45\)?)?)(\s?\d{2}\s?\d{2}\s?\d{2}\s?\d{2})$/
        }
    },
    messages: {
        phone: {
            regex: "Please enter a valid Danish phone number (e.g., +45 12 34 56 78 or 12345678)"
        }
    }
});

Key Details: #

• The regex matches valid Danish formats:
  • Optional country code: +45, (+45), or no country code at all
  • 8 digits, which can be grouped with optional spaces (e.g., 12 34 56 78) or written as a single string (12345678)
• The .trim() ensures accidental leading/trailing spaces don't break validation
• The this.optional(element) check allows empty values if the field isn't marked as required

If you need to pass the regex as a string (e.g., from a config file), escape the backslashes properly:

regex: "^((\\(?\\+45\\)?)?)(\\s?\\d{2}\\s?\\d{2}\\s?\\d{2}\\s?\\d{2})$"

内容的提问来源于stack exchange，提问作者sebastian sledz