PHP第七课 数组的用法2_PHP教程

<?php
								$arr=array("name"=>"user1","age"=>"30","sex"=>"man");


								foreach($arr as $key=>$val){
									$keys[]=$key;
									$vals[]=$val;
								}
									
										echo "<pre class="code">";
										print_r($keys);
										echo "

";
								print_r($vals);
								echo "

<?php
					$arr=array("name"=>"user1","age"=>"30","sex"=>"man");


					$keys=array_values($arr);


					echo "<pre class="code">";
					print_r($keys);
					echo "

<?php
			$arr=array("user1"=>70,60,80,78,34,34,34,56,78,78);


			function older($var){
				return ($var>60);


			}


			$arr2=array_filter($arr,"older");
			
			echo "<pre class="code">";
			print_r($arr2);
			echo "

<?php
		$arr=array("user1"=>10,"b"=>1,"c"=>3,"d"=>30);


		$arr2=array_flip($arr);


		ksort($arr2);


		echo "<pre class="code">";
		print_r($arr2);
		echo "

<?php
		$array1 = $array2 = array("img12.png", "img10.png", "img2.png", "img1.png");


		sort($array1);
		echo "Standard sorting\n";
		print_r($array1);


		natsort($array2);
		echo "\nNatural order sorting\n";
		print_r($array2);
		?> 

<?php
		$arr=array("aaa","bbbbbbbbb","cc","ddddd");
		//需求:
		//1.按照标题长度排序
		//2.标题长度变成标题字符串的key


		//将数组中的value的长度取出,并作为一个新数组
		//strlen($val)取出字符串的长度
		foreach ($arr as  $val) {
			    $lens[]=strlen($val);
			}	


			
			array_multisort($lens,SORT_ASC,$arr);//对数组进行排序,根据第一个数组来排序第二个数组  SORT_ASC表示升序排序


			sort($lens);


			$arr2=array_combine($lens, $arr);//第一个数组作为第二个数组对应的key,返回一个新数组


			echo "<pre class="code">";
			print_r($arr2);
			echo "

<?php


			$str="php,js,html,ces,div";
			$arr=explode(",",$str);


			echo "<pre class="code">";
			print_r($arr);
			echo "

<?php


			$str="php,js,html,ces,div";
			$arr=explode(",",$str);


			$str2=implode("-",$arr);


			echo "<pre class="code">";
			print_r($str2);
			echo "

<?php


				$str="php,js,html,ces,div";
				$arr=explode(",",$str);


				$arr2=array_reverse($arr);//讲数组中的值进行倒序


				$str2=implode("-",$arr2);


				echo "<pre class="code">";
				print_r($str2);
				echo "

<?php
	
				//截取总是从后往前截取
			    $arr = array("aa","bb","cc","dd","ee","ff","gg");


			    $arr2 = array_slice($arr, 0,2);//表示从0的位置截取2个  aa bb
			    $arr3 = array_slice($arr, -3,2);//表示从后往前数到3的位置,开始截取2个//ee  ff


			    echo "<pre class="code">";
			     print_r($arr3);
			     echo "

不仅拆减,而且可以添加

<?php
		    $arr = array("aa","bb","cc","dd","ee","ff","gg");


		    $arr2 = array_splice($arr, 0, 3, array("hh","ii","jj","kk"));//直接取原数组的值,并将原数组进行改变,原数组为取走以后剩下的值


		    echo "<pre class="code">";
		    print_r($arr2);
		    echo "

";
		    print_r($arr);
		    echo "