PHPで改行コードを使うときはシングルクォーテーションでなく、ダブルクォーテーションを使う。文字列を改行コードで分割して配列にするときに、シングルクォーテーションだと予想しないことが起きる。下のコードにあるように改行コードはダブルクォーテーションで囲もう。
<span class="katex"><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.4306em;"></span><span class="mord mathnormal">ro</span><span class="mord mathnormal" style="margin-right:0.02691em;">w</span><span class="mord mathnormal">s</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">e</span><span class="mord mathnormal">x</span><span class="mord mathnormal" style="margin-right:0.01968em;">pl</span><span class="mord mathnormal">o</span><span class="mord mathnormal">d</span><span class="mord mathnormal">e</span><span class="mopen">(</span><span class="mord">"</span><span class="mord text" style="color:#cc0000;"><span class="mord" style="color:#cc0000;">\n</span></span><span class="mord">"</span><span class="mpunct">,</span></span></span></span>input );
テキストエリアの入力を改行で分割して配列にするときは次のようにする。
<span class="katex"><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:0.854em;vertical-align:-0.1944em;"></span><span class="mord mathnormal">in</span><span class="mord mathnormal">p</span><span class="mord mathnormal">u</span><span class="mord mathnormal">t</span><span class="mspace" style="margin-right:0.2778em;"></span><span class="mrel">=</span><span class="mspace" style="margin-right:0.2778em;"></span></span><span class="base"><span class="strut" style="height:1.0019em;vertical-align:-0.25em;"></span><span class="mord mathnormal" style="margin-right:0.10764em;">f</span><span class="mord mathnormal">i</span><span class="mord mathnormal">lt</span><span class="mord mathnormal">e</span><span class="mord"><span class="mord mathnormal" style="margin-right:0.02778em;">r</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3117em;"><span style="top:-2.55em;margin-left:-0.0278em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight">i</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord mathnormal">n</span><span class="mord mathnormal">p</span><span class="mord mathnormal">u</span><span class="mord mathnormal">t</span><span class="mopen">(</span><span class="mord mathnormal" style="margin-right:0.07847em;">I</span><span class="mord mathnormal" style="margin-right:0.13889em;">NP</span><span class="mord mathnormal" style="margin-right:0.10903em;">U</span><span class="mord"><span class="mord mathnormal" style="margin-right:0.13889em;">T</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height:0.3283em;"><span style="top:-2.55em;margin-left:-0.1389em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathnormal mtight" style="margin-right:0.13889em;">P</span></span></span></span><span class="vlist-s"></span></span><span class="vlist-r"><span class="vlist" style="height:0.15em;"><span></span></span></span></span></span></span><span class="mord mathnormal" style="margin-right:0.13889em;">OST</span><span class="mpunct"><span class="mpunct">,</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.7519em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">′</span></span></span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">ro</span><span class="mord mathnormal" style="margin-right:0.02691em;">w</span><span class="mord"><span class="mord mathnormal">s</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.7519em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">′</span></span></span></span></span></span></span></span></span><span class="mclose">)</span><span class="mpunct">;</span></span></span></span>input = str_replace( array( "\r\n", "\r", "\n" ), "\n", <span class="katex"><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">in</span><span class="mord mathnormal">p</span><span class="mord mathnormal">u</span><span class="mord mathnormal">t</span><span class="mclose">)</span><span class="mpunct">;</span></span></span></span>rows = explode( "\n", <span class="katex"><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">in</span><span class="mord mathnormal">p</span><span class="mord mathnormal">u</span><span class="mord mathnormal">t</span><span class="mclose">)</span><span class="mpunct">;</span></span></span></span>rows = array_map( 'trim', <span class="katex"><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1em;vertical-align:-0.25em;"></span><span class="mord mathnormal">ro</span><span class="mord mathnormal" style="margin-right:0.02691em;">w</span><span class="mord mathnormal">s</span><span class="mclose">)</span><span class="mpunct">;</span></span></span></span>rows = array_filter( <span class="katex"><span class="katex-html" aria-hidden="true"><span class="base"><span class="strut" style="height:1.0019em;vertical-align:-0.25em;"></span><span class="mord mathnormal">ro</span><span class="mord mathnormal" style="margin-right:0.02691em;">w</span><span class="mord mathnormal">s</span><span class="mpunct"><span class="mpunct">,</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.7519em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">′</span></span></span></span></span></span></span></span></span><span class="mspace" style="margin-right:0.1667em;"></span><span class="mord mathnormal">s</span><span class="mord mathnormal">t</span><span class="mord mathnormal" style="margin-right:0.02778em;">r</span><span class="mord mathnormal" style="margin-right:0.01968em;">l</span><span class="mord mathnormal">e</span><span class="mord"><span class="mord mathnormal">n</span><span class="msupsub"><span class="vlist-t"><span class="vlist-r"><span class="vlist" style="height:0.7519em;"><span style="top:-3.063em;margin-right:0.05em;"><span class="pstrut" style="height:2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mtight"><span class="mord mtight">′</span></span></span></span></span></span></span></span></span><span class="mclose">)</span><span class="mpunct">;</span></span></span></span>rows = array_values( $rows );
下の三行は、配列から文字のない要素を削除したり、その結果生じるキーのズレを修正したりするどうでもいいコード。
ポイントは改行コードを最初に￥ｎにまとめること。WindowsやMacでは改行コードの扱いに違いがあるので、最初にそれらを一つに統一して、それから￥ｎで分割する。
