PHP面試題附答案

PHP面試題附答案

1.$users[]=john;

2.array_add($users,john);

3.array_push($users,john);

4.$users||=john;

Answer:2,4

2.Whatsthedifferencebetweensort(),asort()andksort(),rsort()?Underwhatcircumstanceswouldyouuseeachofthese?

sort():本函數(shù)對(duì)數(shù)組的值進(jìn)行排序。當(dāng)本函數(shù)結(jié)束時(shí)數(shù)組單元將被從最低到最高重新支配,array中的單元給予新的鍵名。這將刪除原有的鍵名而不僅是重新排序。

asort():這個(gè)函數(shù)將數(shù)組的值重新排序，由小至大排列。數(shù)組的索引亦跟著值的挨次而變動(dòng)。當(dāng)您在程序中需要重新整理數(shù)組值的挨次時(shí)，就可以使用這個(gè)函數(shù)。

ksort():對(duì)數(shù)組根據(jù)鍵名排序，保留鍵名到數(shù)據(jù)的關(guān)聯(lián)。本函數(shù)主要用于關(guān)聯(lián)數(shù)組。

rsort():本函數(shù)對(duì)數(shù)組進(jìn)行逆向排序(最高到最低)。與sort()執(zhí)行相反的操作。

3.Whatwouldthefollowingcodeprinttothebrowser?Why?

$num=10;

functionmultiply(){

$num=$num*10;

}

multiply();

echo$num;

10

4.Whatisthedifferencebetweenareferenceandaregularvariable?Howdoyoupassbyreferencewhywouldyouwantto?

passbyreferencelikethisfunctions($vars);

itlikesmorefast;

5.Whatfunctionscanyouusetoaddlibrarycodetothecurrentlyrunningscript?

inlcude()orrequire();

6.Whatisthedifferencebetweenfoo()@foo()?

iffoo()throwaerror,willbealert,but@foo()no;

7.HowdoyoudebugaPHPapplication?

xdebugorusedie()doit;

8.Whatdoes===do?Whatsanexampleofsomethingthatwillgivetruefor==,butnot===?

===用于精確比較ex:('==null)=truebut('===null)=false;

9.Howwouldyoudeclareaclassnamed"myclass'withnomethodsorproperties?

classmyclass{

}

10.Howwouldyoucreateanobject,whichisaninstanceof"myclass'?

$myoject=newmyclass();

11.Howdoyouaccessandsetpropertiesofaclassfromwithintheclass?

getVar()orsetVar();

12.Whatisthedifferencebetweenincludeinclude_once?includerequire?

require:PHP程式在執(zhí)行前，就會(huì)先讀入require所指定引入的檔案，使它變成PHP程式網(wǎng)頁(yè)的一部份。常用的函式，亦可以這個(gè)方法將它引入網(wǎng)頁(yè)中。錯(cuò)誤產(chǎn)生致命錯(cuò)誤。

include:這個(gè)函式一般是放在流程掌握的處理區(qū)段中。PHP程式網(wǎng)頁(yè)在讀到include的檔案時(shí)，才將它讀進(jìn)來。這種方式，可以把程式執(zhí)行時(shí)的流程簡(jiǎn)潔化。錯(cuò)誤產(chǎn)生警報(bào)。

include_once:此行為和include()語句類似，唯一區(qū)分是假如該文件中的代碼已經(jīng)被包含了，則不會(huì)再次包含。猶如此語句名字示意的那樣，只會(huì)包含一次。

13.Whatfunctionwouldyouusetoredirectthebrowsertoanewpage?

1.redir()

2.header()

3.location()

4.redirect()

2

14.Whatfunctioncanyouusetoopenafileforreadingandwriting?

1.fget();

2.file_open();

3.fopen();

4.open_file();

3

15.Whatsthedifferencebetweenmysql_fetch_row()andmysql_fetch_array()?

mysql_fetch_row():返回依據(jù)所取得的`行生成的數(shù)組，假如沒有更多行則返回FALSE。

mysql_fetch_array():是mysq_fetch_row()的擴(kuò)展版本。除了將數(shù)據(jù)以數(shù)字索引方式儲(chǔ)存在數(shù)組中之外，還可以將數(shù)據(jù)作為關(guān)聯(lián)索引儲(chǔ)存，用字段名作為鍵名。

16.Whatdoesthefollowingcodedo?Explainwhatsgoingonthere.

$date=08/26/2023;

printereg_replace(([0-9]+)/([0-9]+)/([0-9]+),2/1/3,$date);

本函數(shù)以正則的規(guī)章來解析比對(duì)字符串，欲取而代之的字符串為2/1/3。

返回值為字符串類型，為取代后的字符串結(jié)果。

17.Givenalineoftext$string,howwouldyouwritearegularexpressiontostripalltheHTMLtagsfromit?

strip_tags

18.WhatsthedifferencebetweenthewayPHPandPerldistinguishbetweenarraysandhashes?

19.HowcanyougetroundthestatelessnatureofHTTPusingPHP?

20.Whatdoesth