If a variable only contains one word

I would like to know h开发者_运维百科ow I could find out in PHP if a variable only contains 1 word. It should be able to recognise: "foo" "1326" ";394aa", etc.

It would be something like this:

$txt = "oneword";

if($txt == 1 word){ do.this; }else{ do.that; }

Thanks.

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I'm assuming a word is defined as any string delimited by one space symbol

$txt = "multiple words";

if(strpos(trim($txt), ' ') !== false)
{
    // multiple words
}
else
{
    // one word
}

---

What defines one word? Are spaces allowed (perhaps for names)? Are hyphens allowed? Punctuation? Your question is not very clearly defined.

Going under the assumption that you just want to determine whether or not your value contains spaces, try using regular expressions:

http://php.net/manual/en/function.preg-match.php

<?php
$txt = "oneword";

if (preg_match("/ /", $txt)) {
    echo "Multiple words.";
} else {
    echo "One word.";
}
?>

Edit The benefit to using regular expressions is that if you can become proficient in using them, they will solve a lot of your problems and make changing requirements in the future a lot easier. I would strongly recommend using regular expressions over a simple check for the position of a space, both for the complexity of the problem today (as again, perhaps spaces aren't the only way to delimit words in your requirements), as well as for the flexibility of changing requirements in the future.

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Utilize the strpos function included within PHP.

Returns the position as an integer. If needle is not found, strpos() will return boolean FALSE.

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Besides strpos, an alternative would be explode and count:

$txt = trim("oneword secondword");
$words = explode( " ", $txt); // $words[0] = "oneword", $words[1] = "secondword"

if (count($words) == 1) 
    do this for one word
else
    do that for more than one word assuming at least one word is inputted