PHP Regular Expression. Check if String contains ONLY letters

Question

In PHP, how do I check if a String contains only letters? I want to write an if statement that will return false if there is (white space, number, symbol) or anything else other than `a-z` and `A-Z`. My string must contain ONLY letters. I thought I could do it this way, but I'm doing it wrong: ``` if( ereg("[a-zA-Z]+", $myString)) return true; else return false; ``` How do I find out if `myString` contains only letters?

Accepted Answer

Never heard of `ereg`, but I'd guess that it will match on substrings.

In that case, you want to include anchors on either end of your regexp so as to force a match on the whole string:

```
"^[a-zA-Z]+$"
```

Also, you could simplify your function to read

```
return ereg("^[a-zA-Z]+$", $myString);
```

because the `if` to return `true` or `false` from what's already a boolean is redundant.

Alternatively, you could match on any character that's not a letter, and return the complement of the result:

```
return !ereg("[^a-zA-Z]", $myString);
```

Note the `^` at the beginning of the character set, which inverts it. Also note that you no longer need the `+` after it, as a single "bad" character will cause a match.

Finally... this advice is for Java because you have a Java tag on your question. But the `$` in `$myString` makes it look like you're dealing with, maybe Perl or PHP? Some clarification might help.

PHP Regular Expression. Check if String contains ONLY letters

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