SQL中的查看用户权限show grants出现错误
exec sp_addlogin U4,666;
use school exec sp_adduser U4;
grant select on student to U4;
grant select(Teac_id,Teac_name) on Teacher to U4;
show grants for U4;

前面都正常,但是最后一句出现错误,关键字 'for' 附近有语法错误。
我就是想查看已创建用户U4的权限

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D/eglCodecCommon: setVertexArrayObject: set vao to 0 (0) 0 0 D/EGL_emulation: eglCreateContext: 0xe3340b60: maj 3 min 1 rcv 4 D/EGL_emulation: eglMakeCurrent: 0xe3340b60: ver 3 1 (tinfo 0xe338bc10) E/eglCodecCommon: glUtilsParamSize: unknow param 0x000082da glUtilsParamSize: unknow param 0x000082da W/Gralloc3: mapper 3.x is not supported D/: createUnique: call D/: HostConnection::get() New Host Connection established 0xd7d26ad0, tid 23910 HostComposition ext ANDROID_EMU_CHECKSUM_HELPER_v1 ANDROID_EMU_native_sync_v2 ANDROID_EMU_native_sync_v3 ANDROID_EMU_dma_v1 ANDROID_EMU_direct_mem ANDROID_EMU_host_composition_v1 ANDROID_EMU_host_composition_v2 ANDROID_EMU_vulkan ANDROID_EMU_deferred_vulkan_commands ANDROID_EMU_vulkan_null_optional_strings ANDROID_EMU_vulkan_create_resources_with_requirements ANDROID_EMU_YUV420_888_to_NV21 ANDROID_EMU_YUV_Cache GL_OES_EGL_image_external_essl3 GL_OES_vertex_array_object GL_KHR_texture_compression_astc_ldr ANDROID_EMU_gles_max_version_3_1 D/eglCodecCommon: allocate: Ask for block of size 0x1000 D/eglCodecCommon: allocate: ioctl allocate returned offset 0x3ffff6000 size 0x2000 D/EGL_emulation: eglMakeCurrent: 0xe3340b60: ver 3 1 (tinfo 0xe338bc10) D/eglCodecCommon: setVertexArrayObject: set vao to 0 (0) 0 0 I/AssistStructure: Flattened final assist data: 1788 bytes, containing 1 windows, 10 views W/e.myapplicatio: Accessing hidden method Ljava/lang/invoke/LambdaMetafactory;->metafactory(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite; (blacklist, linking, denied) E/AndroidRuntime: FATAL EXCEPTION: Thread-2 Process: com.example.myapplication, PID: 23852 java.lang.NoSuchMethodError: No static method metafactory(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite; in class Ljava/lang/invoke/LambdaMetafactory; or its super classes (declaration of 'java.lang.invoke.LambdaMetafactory' appears in /apex/com.android.runtime/javalib/core-oj.jar) at com.mysql.cj.conf.ConnectionUrl.buildConnectionStringCacheKey(ConnectionUrl.java:246) at com.mysql.cj.conf.ConnectionUrl.getConnectionUrlInstance(ConnectionUrl.java:185) at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:204) at java.sql.DriverManager.getConnection(DriverManager.java:580) at java.sql.DriverManager.getConnection(DriverManager.java:218) at com.example.myapplication.JdbcUtil.getConnection(JdbcUtil.java:22) at com.example.myapplication.UserDao.<init>(UserDao.java:15) at com.example.myapplication.MainActivity$1.run(MainActivity.java:53) at java.lang.Thread.run(Thread.java:919) D/EGL_emulation: eglMakeCurrent: 0xe3340b60: ver 3 1 (tinfo 0xe338bc10) D/AutofillManager: onActivityFinishing(): calling cancelLocked() Process 23852 terminated. ``` 在网上百度了很多方法都没有解决,起初以为是驱动的问题,但是换了一个仍然不好用,求求大神赐教

MySQL Workbench中的数据库权限不一致?

<div class="post-text" itemprop="text"> <p>I am trying to add another user, in addition to <code>root</code> to my database. So, I did the following in MySQL Workbench:</p> <p><img src="https://i.stack.imgur.com/WnbtV.png" alt="enter image description here"></p> <ul> <li><p>clicked on the tab called "Management" shown in picture, and then clicked on "Users and Priveleges".</p></li> <li><p>Then I clicked "add account" in the lower left hand corner, and entered a user name and password, and of course it shows up in the pane on the LHS.</p></li> </ul> <p>However, then I go into the tab called "Schemas", also shown in the piccutre above, and I click on the "i" with a circle around it, as shown in the picture below. </p> <p><img src="https://i.stack.imgur.com/uDiR7.png" alt="enter image description here"></p> <ul> <li>Then, I click on the tab that says "Grants" and see if I'm there. but I'm not. How do I add my username? </li> </ul> <p>I refreshed everything multiple times, so that isn't an issue. </p> <p>The way I got to this problem was: I tried to access the DB using python mysql package, I get the common error:</p> <pre><code>_mysql_exceptions.OperationalError: (1044, "Access denied for user... </code></pre> <p>...which is why I went and added a user and tried to check the grants.</p> <p>How do I change the permissions? Thanks.</p> </div>

用户''@ localhost'拒绝访问

<div class="post-text" itemprop="text"> <p>Hi guys i've been stuck on this issue for the past hour. I've read online that i have to change the privileges for the user on mysql. I have done this and the user has been granted all privileges yet i still get the error! when i enter <code>SHOW GRANTS FOR 'root'@'localhost';</code> it returns with</p> <p><code>+---------------------------------------------------------------------+ | Grants for root@localhost | +---------------------------------------------------------------------+ | GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION | | GRANT PROXY ON ''@'' TO 'root'@'localhost' WITH GRANT OPTION | +---------------------------------------------------------------------+</code> Any help would be much appreciated i just cant seem to find anything that works.</p> </div>

golang —使用用户和密码连接到PostgreSQL时无法创建用户

<div class="post-text" itemprop="text"> <p>I'm trying out the Chitchat go app from the book Go Web Programming. The original version works. When I use a user &amp; password to access postgresql, it can connect to db but fails to create a new User, as shown below:</p> <pre><code>func db() (database *sql.DB) { database, err := sql.Open("postgres", "dbname=chitchat user=tom password=tomahawk sslmode=disable") if err != nil { log.Fatal(err) fmt.Println("Db connection failed") } return } </code></pre> <p>Here's the full code on <a href="https://github.com/mjwong/chitchat" rel="nofollow">Github</a>.</p> <p>However, I've found a temporary solution but it requires granting access to all the sequences in the chitchat database. Even after I've applied a </p> <pre><code>GRANT ALL PRIVILEGES ON DATABASE chitchat to tom; </code></pre> <p>it still requires manual grants to each of the table sequences. Here're the steps taken:</p> <p>1) Grant access to database</p> <pre><code>GRANT all privileges on database chitchat to tom; </code></pre> <p>2) List all sequences in chitchat database</p> <pre><code>SELECT c.relname FROM pg_class c WHERE c.relkind = 'S'; </code></pre> <p>3) Grant access to each of them</p> <pre><code>GRANT all privileges on sequence users_id_seq to tom; GRANT all privileges on sequence threads_id_seq to tom; GRANT all privileges on sequence posts_id_seq to tom; GRANT all privileges on sequence sessions_id_seq to tom; </code></pre> <p>Is there a better way? Thanks in advance.</p> </div>

Android7.0手机和单反相机连接,读取存储目录内容

手机和单反相机连接,发现单反相机根目录的uri如下:content://com.android.mtp.documents/document;但是直接通过contentresolver.query方法报异常: **No persistable permission grants found for UID 10228 and Uri 0 @ content://com.android.mtp.documents/document**

帮助找到这个MySQL页面中的安全漏洞?

<div class="post-text" itemprop="text"> <p>I am trying to find security flaws in a MySQL page. It is an assignment for a class learning about SQL. Through a textbox, they will be given access to a database to submit queries and see if it returns the correct data sets. I want to find out if there's anything malicious they could do.</p> <p>This is the result of a <code>SHOW GRANTS</code> query:</p> <pre><code>Grants for user@localhost GRANT USAGE ON *.* TO 'user'@'localhost' IDENTIFIED BY PASSWORD 'the password' GRANT SELECT ON `server\_dir`.* TO 'user'@'localhost' GRANT SELECT ON `server\_dir\_ans`.* TO 'user'@'localhost' </code></pre> <p>Can someone explain what these <code>GRANT</code> statements mean? What is <code>*.*</code> and <code>GRANT USAGE</code>? What else can I do to this site to break it?</p> <p>The site itself is written in PHP.</p> <p>In response to The Rook, when I execute:</p> <pre><code>UPDATE mysql.user set Password = password("hacked"); FLUSH PRIVILEGES; </code></pre> <p>I get back:</p> <pre><code>Error Number: 1142. UPDATE command denied to user 'user'@'localhost' for table 'user' Error Number: 1227. Access denied; you need the RELOAD privilege for this operation </code></pre> <p>As I thought, it appears that the user lacks permissions necessary to do this. Or am I misunderstanding something?</p> </div>

PHP连接MySQL错误

<div class="post-text" itemprop="text"> <p>I keep on getting this error : Warning: mysqli_connect(): (HY000/1045): Access denied for user '12345'@'localhost' (using password: YES). I have already tried to create a new user, using a password, using no password, granting privileges to new user. I can login to the mysql database using these credentials. I can run every command with them in MySQL, just not connect to PHP. If it matters, this is my php code</p> <pre><code>&lt;? php $dbServername = "localhost"; $dbUsername = "12345"; $dbPassword = "12345"; $dbName = "loginsystem"; $conn = mysqli_connect($dbServername, $dbUsername, $dbPassword, $dbName); When showing grants for user: '12345'@'localhost': mysql&gt; SHOW GRANTS FOR '12345'@'localhost'; +-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Grants for 12345@localhost | +-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, RELOAD, SHUTDOWN, PROCESS, FILE, REFERENCES, INDEX, ALTER, SHOW DATABASES, SUPER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE, REPLICATION SLAVE, REPLICATION CLIENT, CREATE VIEW, SHOW VIEW, CREATE ROUTINE, ALTER ROUTINE, CREATE USER, EVENT, TRIGGER, CREATE TABLESPACE, CREATE ROLE, DROP ROLE ON *.* TO `12345`@`localhost` | | GRANT BACKUP_ADMIN,BINLOG_ADMIN,CONNECTION_ADMIN,ENCRYPTION_KEY_ADMIN,GROUP_REPLICATION_ADMIN,PERSIST_RO_VARIABLES_ADMIN,REPLICATION_SLAVE_ADMIN,RESOURCE_GROUP_ADMIN,RESOURCE_GROUP_USER,ROLE_ADMIN,SET_USER_ID,SYSTEM_VARIABLES_ADMIN,XA_RECOVER_ADMIN ON *.* TO `12345`@`localhost` | +-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 2 rows in set (0.00 sec) </code></pre> <p>/etc/my.cnf file (INSIDE MYSQL) :</p> <pre><code>[mysqld_safe] [mysqld] secure_file_priv="/Users/Steven/" </code></pre> <p>/etc/my.cnf file (INSIDE xAMPP):</p> <pre><code>#password = your_password port = 3306 socket = /Applications/XAMPP/xamppfiles/var/mysql/mysql.sock # Here follows entries for some specific programs # The MySQL server [mysqld] user = mysql port=3307 socket = /Applications/XAMPP/xamppfiles/var/mysql/mysql.sock skip-external-locking key_buffer = 16M max_allowed_packet = 1M table_open_cache = 64 sort_buffer_size = 512K net_buffer_length = 8K read_buffer_size = 256K read_rnd_buffer_size = 512K myisam_sort_buffer_size = 8M innodb_force_recovery = 1 </code></pre> <blockquote> <p>Oh I forgot to mention I did flush privileges and restarts of server.</p> </blockquote> </div>

Apache 2.4上的嵌套RewriteRules导致500错误

<div class="post-text" itemprop="text"> <p>I have a site running on cPanel, where wordpress is installed in the root. I also have a custom application I have written which is located in a subfolder named 'gallery'. Within the gallery subfolder is an 'admin' folder. The root folder of gallery (no rewrite) controls the display of information, where the root of 'gallery/admin' grants the user administrative access to the application. The path structure is redirected and handled (custom MVC framework), which is primarily directed by the following .htaccess directives :</p> <p>Require all granted</p> <pre><code>RewriteEngine On RewriteCond %{REQUEST_URI} !\.(jpg|png|bmp|gif|css|js|map|ttf|woff|woff2|svg|eot)$ RewriteRule ^(.*)$ controller.php?page=$1 [NC,L,QSA] RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-f RewriteRule ^(.*)$ controller.php?page=error&amp;rewritten=1&amp;missing=$1 [NC,L,QSA] </code></pre> <p>The .htaccess for wordpress is customized for compression, expiring/caching of different types, in addition to handling traditional wordpress stuff and is as follows (pasting in full) :</p> <pre><code>Options -Indexes # BEGIN WordPress # Expires Caching (Leverage Browser Caching) &lt;IfModule mod_expires.c&gt; ExpiresActive On ExpiresByType image/jpg "access 2 week" ExpiresByType image/jpeg "access 2 week" ExpiresByType image/gif "access 2 week" ExpiresByType image/png "access 2 week" ExpiresByType text/css "access 2 week" ExpiresByType application/pdf "access 2 week" ExpiresByType text/x-javascript "access 2 week" ExpiresByType application/x-shockwave-flash "access 2 week" ExpiresByType image/x-icon "access 2 week" ExpiresDefault "access 2 week" &lt;/IfModule&gt; # Enable GZIP Compression (compress text, html, javascript, css, xml and so on) ## &lt;ifModule mod_gzip.c&gt; mod_gzip_on Yes mod_gzip_dechunk Yes mod_gzip_item_include file \.(html?|txt|css|js|pl)$ mod_gzip_item_include handler ^cgi-script$ mod_gzip_item_include mime ^text/.* mod_gzip_item_include mime ^application/x-javascript.* mod_gzip_item_exclude mime ^image/.* mod_gzip_item_exclude rspheader ^Content-Encoding:.*gzip.* &lt;/ifModule&gt; &lt;IfModule mod_deflate.c&gt; AddOutputFilterByType DEFLATE text/plain AddOutputFilterByType DEFLATE text/html #AddOutputFilterByType DEFLATE text/xml AddOutputFilterByType DEFLATE text/css AddOutputFilterByType DEFLATE application/javascript AddOutputFilterByType DEFLATE application/x-javascript &lt;/IfModule&gt; &lt;IfModule mod_rewrite.c&gt; RewriteEngine On RewriteCond %{HTTP_HOST} !^www\.example\.org RewriteRule (.*) http://www.example.org/$1 [R=301,L] #RewriteBase / RewriteRule ^index\.php$ - [L] RewriteRule ^sitemap.xml /sitemap.php?p=xml [L] RewriteRule ^sitemap.xsl /sitemap.php?p=xsl [L] RewriteRule ^sitemap.css /sitemap.php?p=css [L] RewriteRule ^sitemap.js /sitemap.php?p=js [L] RewriteRule ^robots.txt /sitemap.php?p=txt [L] RewriteRule ^gallery - [L] RewriteRule ^controller\.php$ - [L] RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule . /index.php [L] &lt;/IfModule&gt; # END WordPress </code></pre> <p>The reason behind the double check <code>RewriteCond %{REQUEST_FILENAME} !-f</code> was because of another issue I had when trying to handle only files of a specific type where the file does not exist physically. (pretty 404 not found page when jpg/etc are missing).</p> <p>As you can see, <code>controller.php</code> does all the grunt work for authentication, etc. If I comment out any of the lines containing <code>^(.*)$ controller.php?</code> I don't get 500 errors unless I call the controller directly and let it redirect based on the application root path.</p> <p>This works flawlessly on my Debian 8, and Ubuntu 11 boxes, as well as on Windows 10. The admin is based on the open source project <a href="https://github.com/microvb/otp-thing" rel="nofollow">otp-thing</a> and works well. Just am having some trouble handling the redirects when the almighty wordpress is in the root of the site.</p> <p>There doesn't appear to be any code issues (if so, they would have cropped up in other tests on Debian 8, Ubuntu 11, and especially Windows 10).</p> <p>The server software running on this build of cPanel are as follows :</p> <pre><code>Server version: Apache/2.4.18 (Unix) Server built: Mar 1 2016 10:43:46 Cpanel::Easy::Apache v3.32.10 rev9999 Server's Module Magic Number: 20120211:52 Server loaded: APR 1.5.2, APR-UTIL 1.5.4 Compiled using: APR 1.5.2, APR-UTIL 1.5.4 Architecture: 64-bit Server MPM: prefork threaded: no forked: yes (variable process count) Server compiled with.... -D APR_HAS_SENDFILE -D APR_HAS_MMAP -D APR_HAVE_IPV6 (IPv4-mapped addresses disabled) -D APR_USE_SYSVSEM_SERIALIZE -D APR_USE_PTHREAD_SERIALIZE -D SINGLE_LISTEN_UNSERIALIZED_ACCEPT -D APR_HAS_OTHER_CHILD -D AP_HAVE_RELIABLE_PIPED_LOGS -D DYNAMIC_MODULE_LIMIT=256 -D HTTPD_ROOT="/usr/local/apache" -D SUEXEC_BIN="/usr/local/apache/bin/suexec" -D DEFAULT_PIDLOG="logs/httpd.pid" -D DEFAULT_SCOREBOARD="logs/apache_runtime_status" -D DEFAULT_ERRORLOG="logs/error_log" -D AP_TYPES_CONFIG_FILE="conf/mime.types" -D SERVER_CONFIG_FILE="conf/httpd.conf" </code></pre> <p>And PHP</p> <pre><code>PHP 5.6.18 (cli) (built: Mar 1 2016 10:47:52) Copyright (c) 1997-2016 The PHP Group Zend Engine v2.6.0, Copyright (c) 1998-2016 Zend Technologies with the ionCube PHP Loader v4.7.5, Copyright (c) 2002-2014, by ionCube Ltd., and with Zend Guard Loader v3.3, Copyright (c) 1998-2014, by Zend Technologies </code></pre> <p>Also, if you look at the project source for otp-thing, you will notice some of the nested directories intentionally block public access (app/cache, app/templates_c, etc)</p> <p>The error that is reported by Apache in <code>/usr/local/apache/error_log</code> is :</p> <blockquote> <p>[Thu Aug 25 21:33:21.323468 2016] [core:error] [pid 15805] [client XX.XX.XX.XX:XXXXX] AH00124: Request exceeded the limit of 10 internal redirects due to probable configuration error. Use 'LimitInternalRecursion' to increase the limit if necessary. Use 'LogLevel debug' to get a backtrace.</p> </blockquote> <p><strong>The message is identical if I comment out any combination of the <code>RewriteRule</code> lines from the <code>gallery/admin/.htaccess</code> file.</strong></p> <p>I have tried adding had paths preceding 'controller.php', however this exacerbates the problem, but overall, no change to the issue at hand here.</p> <p>What can I do to make sure that all this stuff works, or even as a workaround, how can I move the htaccess rules for otp-thing into the wordpress htaccess file as above by merging them (how can the directives be adjusted).</p> </div>

验证对API的访问权限

<div class="post-text" itemprop="text"> <p>I'm trying to make my First API, I never did and API before. I did read a couple of documentations but couldn't find something simple enough to describe the authentication process.</p> <p>How do I authenticate a user through an API? like how can I give app developers a way so that they make a login form that grants their users access to their info on my database, and for me to provide data based on the user logged in.</p> <p>I'm confused with the idea of authenticating users through an API, how can they send they passwords securely?</p> </div>

错误400 OAuth2 Google云存储-Go Lang

<div class="post-text" itemprop="text"> <pre><code>// datastore1 package main import ( "fmt" "io/ioutil" "log" "time" "golang.org/x/net/context" "golang.org/x/oauth2/google" "google.golang.org/cloud" "google.golang.org/cloud/datastore" ) const ( // ScopeDatastore grants permissions to view and/or manage datastore entities copeDatastore = "https://www.googleapis.com/auth/datastore" // ScopeUserEmail grants permission to view the user's email address. // It is required to access the datastore. ScopeUserEmail = "https://www.googleapis.com/auth/userinfo.email" ) type ehrEntity struct { email *datastore.Key firstname string lastname string address string age int8 dateofbirth time.Time sex bool } func getCtx() *datastore.Client { // Initialize an authorized transport with Google Developers Console // JSON key. Read the google package examples to learn more about // different authorization flows you can use. // http://godoc.org/golang.org/x/oauth2/google jsonKey, err := ioutil.ReadFile("filename.json") opts, err := google.JWTConfigFromJSON( jsonKey, datastore.ScopeDatastore, datastore.ScopeUserEmail, ) if err != nil { log.Fatal(err) } ctx := context.Background() client, err := datastore.NewClient(ctx, "xxxx", cloud.WithTokenSource(opts.TokenSource(ctx))) if err != nil { log.Fatal(err) } // Use the context (see other examples) return client } func ExampleGet() { ctx := context.Background() client, err := datastore.NewClient(ctx, "xxxx") if err != nil { log.Fatal(err) } key := datastore.NewKey(ctx, "User", "tluu@abc.com", 0, nil) ehr := ehrEntity{ nil, "tri", "luu", "addr1", 20, time.Date(2009, time.January, 10, 23, 0, 0, 0, time.UTC), false} if err := client.Get(ctx, key, ehr); err != nil { log.Fatal(err) } } func main() { getCtx() fmt.Println("Pass authentication") ExampleGet() } </code></pre> <p>When I run go file, It return error follow:</p> <p>Pass authentication (Pass getCtx() function).</p> <p>Error in ExampleGet() May be at </p> <pre><code>ctx := context.Background() client, err := datastore.NewClient(ctx, "xxxx") if err != nil { log.Fatal(err) } </code></pre> <p>Error: 2016/01/09 22:08:43 Post <a href="https://www.googleapis.com/datastore/v1beta2/datasets/xxxx/lookup" rel="nofollow">https://www.googleapis.com/datastore/v1beta2/datasets/xxxx/lookup</a>: oauth2: cannot fetch token: 400 Bad Request Response: { "error" : "invalid_grant" }</p> <p>How to resolve this error?</p> </div>

用localhost和127.0.0.1通过php连接mysql均不成功

win10,64位配置了一个apache2.4.17+php7.0.0+mysql5.7.10的环境,改默认端口为8080,测试是否配置成功时编写了两个php代码, 一个用来测试php和apache的文件info.php,用localhost:8080和127.0.0.1:8080均能正常显示信息,如下图 ![图片说明](https://img-ask.csdn.net/upload/201709/03/1504421804_153640.png) 另一个用来测mysql的文件sql.php如下,密码和用户和mysql吻合,但用localhost和127.0.0.1两者均打不开,一直显示正待等待响应,不知道为啥..... <?php $con=mysqli_connect('localhost:8080','root','password'); if(!$con) echo "失败!"; else echo "成功!"; mysqli_close($con); ?> ![图片说明](https://img-ask.csdn.net/upload/201709/03/1504421816_742069.png) 并且,local host和127.0.0.1有时候都能正常打开,有时候只能某一个正常工作,有时候两个都开不了(都是在apache正常工作时).....也不知道为啥.... 求大神解惑~十分感谢! 更多 0

php下载链接返回内部服务器错误

<div class="post-text" itemprop="text"> <p>i'm try to create download link in my form so people can download the files in the upload folder.I'm used code below</p> <pre><code>&lt;?php $path = $_SERVER['DOCUMENT_ROOT']."/content/uploads/"; // change the path to fit your websites document structure $fullPath = $path.basename($_REQUEST['download_file']); if (is_readable ($fullPath)) { $fsize = filesize($fullPath); $path_parts = pathinfo($fullPath); $ext = strtolower($path_parts["extension"]); switch ($ext) { case "pdf"||"docx"||"doc"||"jpg"||"jpeg": header(("Content-type: lappication/pdf")||("Content-type: application/msword")||("Content-type: image/jpeg")); // add here more headers for diff. extensions header("Content-Disposition: attachment; filename=\"".$path_parts["basename"]."\""); // use 'attachment' to force a download break; default; header("Content-type: application/octet-stream"); header("Content-Disposition: filename=\"".$path_parts["basename"]."\""); } header("Content-length: $fsize"); header("Cache-control: private"); //use this to open files directly readfile($fullPath); exit; } else { die("Invalid request"); } </code></pre> <p>and then i test by put download link in my form</p> <pre><code>&lt;h2&gt;Forms Available&lt;/h2&gt; &lt;a href="content/grants/download.php?download_file=some.pdf"&gt;Download here&lt;/a&gt; &lt;a href="content/grants/download.php?download_file="&gt;Download here&lt;/a&gt; &lt;a href="content/grants/download.php?download_file=IntroLetter.docx"&gt;Download here&lt;/a&gt; &lt;a href="content/grants/download.php?download_file=Conference Grant Application Form.doc"&gt;Download here&lt;/a&gt; </code></pre> <p>from that 4 download link. the first 1 return "invalid request" which i know because that file doesn't exist. second link pop up download box to download empty file. which i bet because it really empty. for third and fourth link that file really exist in the folder but it return</p> <p>Internal Server Error</p> <p>The server encountered an internal error or misconfiguration and was unable to complete your request.</p> <p>Please contact the server administrator, webmaster@miitresearch-postgraduates.com and inform them of the time the error occurred, and anything you might have done that may have caused the error.</p> <p>More information about this error may be available in the server error log.</p> <p>Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request</p> <p>what could be the problem? TQ :)</p> </div>

大学四年自学走来,这些私藏的实用工具/学习网站我贡献出来了

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