获取可选冒号前的所有字母

Question

I have a wrapper for PHPExcel, and I have a method called setColumn(), which looks like this:

public function setColumn($cell = ""){
    if(empty($cell)){
        $cell = $this->cell;
    }
    $this->column = strtoupper(preg_replace("/[^A-Za-z]/", "", $cell));
    $this->cell   = "{$this->column}{$this->row}";
    return $this;
}

It works just fine, but as I use it, I can pass in ranges such as A1:D1 and when I do, my preg_replace will not replace correctly, it will return AD which I don't want. I want it to return A. I am not sure of the regular expression needed to accomplish this.

The parameter $cell can contain a few different values:

• A1 should return A
• A1:D10 should return A
• AD10 should return AD
• AD1:BBB1 should return AD

The list could go on, but that is the basics. So what can I do to acomplish that?

Answer 1

Try:

preg_replace("/^([A-Z]+).*$/", "$1", $cell)

It'll 'save' the first part and remove everything else.

regex101 demo.