search
HomeBackend DevelopmentPHP Tutorial为何mysql_fetch_array没有执行?

error_reporting(0);
$conn=mysql_connect("localhost","root","root");//填写数据库连接信息
mysql_select_db("a1209173000");//填写数据库名
$valA = $_POST["valA"];
if($valA!=""){
$sql = "select * from  table where chepai='".$valA."'";
$result=mysql_query($sql);
    while($arr=mysql_fetch_array($result))
      {
        echo $arr["name"]."
";
      }
}else{
?>


输入A值:


}
?>

通过在每行后面加echo输出,发现执行到 while($arr=mysql_fetch_array($result))这时里面的没有执行,哪出问题了呢, $sql正常

回复讨论(解决方案)

你是取不到$valA = $_POST["valA"];这个值

$result=mysql_query($sql);if(mysql_error()){  echo mysql_errno() . ": " . mysql_error() . "\n";}

看看有没有报错?

$result=mysql_query($sql);if(mysql_error()){  echo mysql_errno() . ": " . mysql_error() . "\n";}

看看有没有报错?

果然是
1064: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '??AUQ005' at line 1
我在文本框里输入了汉字,结果获取时成了乱码,但echo $valA的时候,结果是 豫AUQ005。  这是不是网页编码没设置的原因啊?  请问PHP怎么设置

$valA是正确的,echo  $sql的时候也没什么错误, 但就是执行的时候,那个汉字出错了

你是取不到$valA = $_POST["valA"];这个值

谢谢,按照mumubangditu的方法,发现是我输入的条件中汉字,而汉字没有被成功识别,请问怎么解决啊。


mysql_select_db("a1209173000");//填写数据库名
之后,加入
mysql_query('set names gbk');
这是被操作的数据与数据库默认字符集不一致造成的


mysql_select_db("a1209173000");//填写数据库名
之后,加入
mysql_query('set names gbk');
这是被操作的数据与数据库默认字符集不一致造成的

谢谢版主, 解决了

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
PHP Dependency Injection Container: A Quick StartPHP Dependency Injection Container: A Quick StartMay 13, 2025 am 12:11 AM

APHPDependencyInjectionContainerisatoolthatmanagesclassdependencies,enhancingcodemodularity,testability,andmaintainability.Itactsasacentralhubforcreatingandinjectingdependencies,thusreducingtightcouplingandeasingunittesting.

Dependency Injection vs. Service Locator in PHPDependency Injection vs. Service Locator in PHPMay 13, 2025 am 12:10 AM

Select DependencyInjection (DI) for large applications, ServiceLocator is suitable for small projects or prototypes. 1) DI improves the testability and modularity of the code through constructor injection. 2) ServiceLocator obtains services through center registration, which is convenient but may lead to an increase in code coupling.

PHP performance optimization strategies.PHP performance optimization strategies.May 13, 2025 am 12:06 AM

PHPapplicationscanbeoptimizedforspeedandefficiencyby:1)enablingopcacheinphp.ini,2)usingpreparedstatementswithPDOfordatabasequeries,3)replacingloopswitharray_filterandarray_mapfordataprocessing,4)configuringNginxasareverseproxy,5)implementingcachingwi

PHP Email Validation: Ensuring Emails Are Sent CorrectlyPHP Email Validation: Ensuring Emails Are Sent CorrectlyMay 13, 2025 am 12:06 AM

PHPemailvalidationinvolvesthreesteps:1)Formatvalidationusingregularexpressionstochecktheemailformat;2)DNSvalidationtoensurethedomainhasavalidMXrecord;3)SMTPvalidation,themostthoroughmethod,whichchecksifthemailboxexistsbyconnectingtotheSMTPserver.Impl

How to make PHP applications fasterHow to make PHP applications fasterMay 12, 2025 am 12:12 AM

TomakePHPapplicationsfaster,followthesesteps:1)UseOpcodeCachinglikeOPcachetostoreprecompiledscriptbytecode.2)MinimizeDatabaseQueriesbyusingquerycachingandefficientindexing.3)LeveragePHP7 Featuresforbettercodeefficiency.4)ImplementCachingStrategiessuc

PHP Performance Optimization Checklist: Improve Speed NowPHP Performance Optimization Checklist: Improve Speed NowMay 12, 2025 am 12:07 AM

ToimprovePHPapplicationspeed,followthesesteps:1)EnableopcodecachingwithAPCutoreducescriptexecutiontime.2)ImplementdatabasequerycachingusingPDOtominimizedatabasehits.3)UseHTTP/2tomultiplexrequestsandreduceconnectionoverhead.4)Limitsessionusagebyclosin

PHP Dependency Injection: Improve Code TestabilityPHP Dependency Injection: Improve Code TestabilityMay 12, 2025 am 12:03 AM

Dependency injection (DI) significantly improves the testability of PHP code by explicitly transitive dependencies. 1) DI decoupling classes and specific implementations make testing and maintenance more flexible. 2) Among the three types, the constructor injects explicit expression dependencies to keep the state consistent. 3) Use DI containers to manage complex dependencies to improve code quality and development efficiency.

PHP Performance Optimization: Database Query OptimizationPHP Performance Optimization: Database Query OptimizationMay 12, 2025 am 12:02 AM

DatabasequeryoptimizationinPHPinvolvesseveralstrategiestoenhanceperformance.1)Selectonlynecessarycolumnstoreducedatatransfer.2)Useindexingtospeedupdataretrieval.3)Implementquerycachingtostoreresultsoffrequentqueries.4)Utilizepreparedstatementsforeffi

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

MinGW - Minimalist GNU for Windows

MinGW - Minimalist GNU for Windows

This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

Dreamweaver Mac version

Dreamweaver Mac version

Visual web development tools

MantisBT

MantisBT

Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

WebStorm Mac version

WebStorm Mac version

Useful JavaScript development tools

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment