Question

我的哈希数组如下：

[
  {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!107", :name=>"Folder 11", :type=>"folder"},
  {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!105", :name=>"Pictures", :type=>"album"}, 
  {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!113", :name=>"Public", :type=>"folder"}, 
  {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!124", :name=>"sasd", :type=>"folder"}, 
  {:id=>nil, :name=>nil, :type=>nil}, 
  {:id=>nil, :name=>nil, :type=>nil},
  {:id=>nil, :name=>nil, :type=>nil},
  {:id=>nil, :name=>nil, :type=>nil}, 
  {:id=>nil, :name=>nil, :type=>nil}, 
  {:id=>nil, :name=>nil, :type=>nil}, 
  {:id=>nil, :name=>nil, :type=>nil}
]

如果我的哈希nil中id为nil，如何删除<!doctype html> <html> <head> <title>Test</title> </head> <body> <form method="post" enctype="multipart/form-data"> <input type="text" name="Filename"> <input type="file" name="my_file[]" multiple> <input type="submit" value="Upload"> </form> <?php if (isset($_FILES['my_file'])) { $myFile = $_FILES['my_file']; $fileCount = count($myFile["name"]); $Filename=$_POST['Filename']; $structure = "Uploads/SystemConfiguration/$Filename"; if (!mkdir($structure, 0777, true)) { die('Failed to create folders...'); } for ($i = 0; $i < $fileCount; $i++) { $name = $_FILES["my_file"]["name"][$i]; $tmp_name=$_FILES["my_file"]["tmp_name"][$i]; move_uploaded_file($tmp_name,"$structure/$name"); ?> <p>File #<?= $i+1 ?>:</p> <p> Name: <?= $myFile["name"][$i] ?><br> Temporary file: <?= $myFile["tmp_name"][$i] ?><br> Type: <?= $myFile["type"][$i] ?><br> Size: <?= $myFile["size"][$i] ?><br> Error: <?= $myFile["error"][$i] ?><br> print "Your file upload was successful and can be seen/downloaded <a href='./uploads/systemconifguration/$Filename'>here</a> </p> <?php } } ?> </body> </html>值？

Answer 1

您可以使用reject：

select

Demo

或arr.select { |h| h[:id] }：

nil

Demo

Answer 2

如果您关注删除元素哪个哈希id为nil，那么最好使用 delete_if

array.delete_if { |h| h[:id].nil? }
 => [
      {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!107", :name=>"Folder 11", :type=>"folder"}, 
      {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!105", :name=>"Pictures", :type=>"album"},
      {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!113", :name=>"Public", :type=>"folder"}, 
      {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!124", :name=>"sasd", :type=>"folder"}
    ]

注意： reject将返回一个新数组，其中包含self中给定块不是true的项目。虽然delete_if会删除self的每个元素，但哪个块的评估结果为true。

Answer 3

我假设您希望得到其值不是全部arr = [{:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!107", :name=>"Folder 11", :type=>"folder"}, {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!105", :name=>"Pictures", :type=>"album"}, {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!113", :name=>"Public", :type=>"folder"}, {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!124", :name=>"sasd", :type=>"folder"}, {:id=>nil, :name=>nil, :type=>nil}, {:id=>nil, :name=>nil, :type=>nil}, {:id=>nil, :name=>nil, :type=>nil}, {:id=>nil, :name=>nil, :type=>nil}, {:id=>nil, :name=>nil, :type=>nil}, {:id=>nil, :name=>nil, :type=>nil}, {:id=>nil, :name=>nil, :type=>nil}] arr.find_all { |h| !h.values.compact.empty? } # => [{:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!107", :name=>"Folder 11", :type=>"folder"}, {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!105", :name=>"Pictures", :type=>"album"}, {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!113", :name=>"Public", :type=>"folder"}, {:id=>"folder.cecb8eb83d90dbeb.CECB8EB83D90DBEB!124", :name=>"sasd", :type=>"folder"}]的所有哈希值。你可以通过以下方式做到：

 java.lang.IndexOutOfBoundsException: Invalid index 2, size is 0
            at java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255)
            at java.util.ArrayList.get(ArrayList.java:308)
            at com.serpentcs.artlovers.main.CustomCursorAdapter$CustomPagerAdapter.instantiateItem(CustomCursorAdapter.java:329)
            at android.support.v4.view.ViewPager.addNewItem(ViewPager.java:869)
            at android.support.v4.view.ViewPager.populate(ViewPager.java:1085)
            at android.support.v4.view.ViewPager.populate(ViewPager.java:951)
            at android.support.v4.view.ViewPager$3.run(ViewPager.java:250)
            at android.view.Choreographer$CallbackRecord.run(Choreographer.java:767)
            at android.view.Choreographer.doCallbacks(Choreographer.java:580)
            at android.view.Choreographer.doFrame(Choreographer.java:549)
            at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:753)
            at android.os.Handler.handleCallback(Handler.java:739)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5254)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)

Answer 4

您想使用select method过滤数组。

list = list.select { |item| item[:id] != nil }

从哈希数组中删除nil值

4 个答案: