Case Study PHP Array Query_PHP Tutorial

When learning PHP arrays, you may encounter problems. Here we will introduce PHP array queries and share them with you here. There are more than 30 new array-related functions in PHP4.0. Many of these general functions allow you to check whether a specific object exists in a given array, count array elements, add or remove elements, or sort elements.

If you have a large array and all you want to accomplish is to find a given value that exists, you can use in_array() to return true or false. The following code will output "Not found in this array" - because you will be looking for an "Alber" in $namesArray that does not exist. You can add elements to any array, either at the beginning or end of an existing array. You can also use functions to create a new array containing two or more array elements. When merged each array will be in the desired order. If your array already has internal sorting, you will need to reorder the new merged array.

PHP array query code:

<ol class="dp-xml">
<li class="alt"><span><span>/**  </span></span></li>
<li class=""><span>*倒序数组  </span></li>
<li class="alt"><span>*@paramaInputarray要排序的数组  </span></li>
<li class=""><span>*@param$bystring排序对象,key为按数组下标排序,value为按值排序  </span></li>
<li class="alt"><span>*/  </span></li>
<li class="">
<span>functionaryReverts($aInput,$</span><span class="attribute"><font color="#ff0000">by</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">'key'</font></span><span>){  </span>
</li>
<li class="alt"><span>if(!is_array($aInput)){  </span></li>
<li class=""><span>returnfalse;  </span></li>
<li class="alt"><span>}  </span></li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">res</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">array</font></span><span>();  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">n</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">count</font></span><span>($aInput);  </span>
</li>
<li class="">
<span>for($</span><span class="attribute"><font color="#ff0000">i</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">0</font></span><span>;$i</span><span class="tag"><strong><font color="#006699"><</FONT></STRONG></SPAN><SPAN>$n;$i++){  </SPAN></SPAN><LI class=alt><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>tmMax</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>getMax</FONT></SPAN><SPAN>($aInput,$by);  </SPAN></SPAN><LI class=""><SPAN>print_r($tmMax);  </SPAN><LI class=alt><SPAN>list($k,$v)=each($tmMax);  </SPAN><LI class=""><SPAN>$res[$k]=$v;  </SPAN><LI class=alt><SPAN>}  </SPAN><LI class=""><SPAN>return$res;  </SPAN><LI class=alt><SPAN>}  </SPAN><LI class=""><SPAN> </SPAN><LI class=alt><SPAN> </SPAN><LI class=""><SPAN>/**  </SPAN><LI class=alt><SPAN>*@paramaInputarray要冒沟的数组  </SPAN><LI class=""><SPAN>*@param$bystring排序对象,key为按数组下标排序,value为按值排序  </SPAN><LI class=alt><SPAN>*/  </SPAN><LI class=""><SPAN>functiongetMax(&$aInput,$by){  </SPAN><LI class=alt><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>max</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>null</FONT></SPAN><SPAN>;  </SPAN></SPAN><LI class=""><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>maxKey</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>null</FONT></SPAN><SPAN>;  </SPAN></SPAN><LI class=alt><SPAN>if($</SPAN><SPAN class=attribute><FONT color=#ff0000>by</FONT></SPAN><SPAN>=='key')  </SPAN></SPAN><LI class=""><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>tar</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>'k'</FONT></SPAN><SPAN>;  </SPAN></SPAN><LI class=alt><SPAN>else  </SPAN><LI class=""><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>tar</FONT></SPAN><SPAN>=</SPAN><SPAN class=attribute-value><FONT color=#0000ff>'v'</FONT></SPAN><SPAN>;  </SPAN></SPAN><LI class=alt><SPAN>foreach($aInputas$</SPAN><SPAN class=attribute><FONT color=#ff0000>k</FONT></SPAN><SPAN>=</SPAN><SPAN class=tag><STRONG><FONT color=#006699>></font></strong></span><span>$v){  </span>
</li>
<li class="">
<span>if($$tar</span><span class="tag"><strong><font color="#006699">></font></strong></span><span>$max){  </span>
</li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">max</font></span><span>=$$tar;  </span>
</li>
<li class="">
<span>$</span><span class="attribute"><font color="#ff0000">maxKey</font></span><span>=$k;  </span>
</li>
<li class="alt"><span>}  </span></li>
<li class=""><span>}  </span></li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">maxValue</font></span><span>=$aInput[$maxKey];  </span>
</li>
<li class=""><span>unset($aInput[$maxKey]);  </span></li>
<li class="alt">
<span>returnarray($</span><span class="attribute"><font color="#ff0000">maxKey</font></span><span>=</span><span class="tag"><strong><font color="#006699">></font></strong></span><span>$maxValue);  </span>
</li>
<li class=""><span>}  </span></li>
<li class="alt"><span> </span></li>
<li class=""><span> </span></li>
<li class="alt">
<span>$</span><span class="attribute"><font color="#ff0000">list</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">array</font></span><span>('apple'=</span><span class="tag"><strong><font color="#006699">></font></strong></span><span>300,'orange'=</span><span class="tag"><strong><font color="#006699">></font></strong></span><span>150,'banana'=</span><span class="tag"><strong><font color="#006699">></font></strong></span><span>100,'mango'=</span><span class="tag"><strong><font color="#006699">></font></strong></span><span>330);  </span>
</li>
<li class="">
<span>echo'</span><strong><font color="#006699"><span class="tag"><</SPAN><SPAN class=tag-name>xmp</SPAN><SPAN class=tag>></span></font></strong><span>';  </span>
</li>
<li class="alt"><span>print_r(aryReverts($list,'value')); </span></li>
</ol>

http://www.bkjia.com/PHPjc/446541.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/446541.htmlTechArticleWhen learning PHP arrays, you may encounter problems. PHP array queries will be introduced here. Take them out here and Share it with everyone. There are more than 30 new array-related functions in PHP4.0. Among them...