Bitcoin Address Verification: A Guide
Bitcoin addresses are unique, 34-character strings that identify a specific transaction on the Bitcoin network. To verify whether a given address is valid or not, you need to check whether it meets certain criteria. In this article, we will provide you with both JavaScript and Java code snippets to help you achieve this.
What makes an address valid?
An Ethereum address is considered valid only if:
- It starts with one or two digits (0-9).
- The next 31 characters are either lowercase letters (a-z) or uppercase letters (A-Z), numbers (0-9), and hyphens (-).
- It does not contain any special characters such as !, @, #, $, etc.
JavaScript code snippet:
function isValidEthereumAddress(address) {
// Check if address starts with one or two digits
if ( address . length < 2 || address [ 0 ] !== '0 ' && address [ 0 ] !== '1 ' ) { .
return false ;
} }
// Check if next 31 characters are valid
for ( let i = 1 ; i <= 31 ; i ++ ) {
const charCode = address.charCodeAt(i);
if ((CharCode < 48 || CharacterCode > 57) && CharacterCode !== -1 && CharacterCode !== 127) {;
return false ;
} }
} }
// Check for special characters
for ( light i = 0 ; i <= 31 ; i ++ ) {
const charCode = address.charCodeAt(i);
if ((Charactercode < 48 || Charactercode > 57) && Charactercode !== -1 && Charactercode !== 127) {
return false ;
} }
} }
// If all checks pass, the address is valid
return true ;
} }
Java code snippet:
public class EthereumAddressValidator {
public static boolean isValidEthereumAddress( String address ) { ;
if ( address . length ( ) < 2 || address . substring ( 0 , 1 ) . equals ( " 0 " ) ||
address.substring(0, 1).equals("1")) {
return false ;
} }
for ( int i = 1 ; i <= 31 ; i ++ ) {
int charCode = address.charAt(i) - '0';
if ( charCode < 48 || charCode > 57 || charCode != -1
|| charCode != 127) {
return false ;
} }
} }
for ( int i = 0 ; i <= 31 ; i ++ ) {
int charCode = address.charAt(i) - '0';
if (( charCode < 48 || charCode > 57 ) && charCode != -1 && charCode != 127 ) { ;
return false ;
} }
} }
// If all checks pass, the address is valid
return true ;
} }
public static void main ( String [] args ) { ;
System.out.println(isValidEthereumAddress("123abc")); // true
System.out.println(isValidEthereumAddress("1abc")); // false (0 is not a digit)
System.out.println(isValidEthereumAddress("123abc!")); // false (special character)
} }
} }
Test cases:
- Valid addresses: “123abc”, “1abc”
- Invalid addresses:
+ “12abc” (first digit is missing, second or third character should be a digit)
+ “abc!” (contains special characters)
Please note that these code snippets only validate Ethereum addresses and do not take other blockchain networks into account. Also, keep in mind that some JavaScript implementations may require additional library dependencies to work properly.
Hope this helps! If you have any further questions or if there is anything else I can help you with, please let us know.