How to check a string starts with numeric number?

I have a string which contains alphanumeric character.

I need to check whether the string is started with number.

Thanks,

See the isDigit(char ch) method:

https://docs.oracle.com/javase/1.5.0/docs/api/java/lang/Character.html

and pass it to the first character of the String using the String.charAt() method.

Character.isDigit(myString.charAt(0));

Sorry I didn't see your Java tag, was reading question only. I'll leave my other answers here anyway since I've typed them out.

Java

String myString = "9Hello World!";
if ( Character.isDigit(myString.charAt(0)) )
{
    System.out.println("String begins with a digit");
}

C++:

string myString = "2Hello World!";

if (isdigit( myString[0]) )
{
    printf("String begins with a digit");
}

Regular expression:

\b[0-9]

Some proof my regex works: Unless my test data is wrong? alt text

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