{"id":124,"date":"2016-07-22T09:56:53","date_gmt":"2016-07-22T01:56:53","guid":{"rendered":"http:\/\/www.secondsend.com\/wordpress\/?p=124"},"modified":"2016-07-22T09:56:53","modified_gmt":"2016-07-22T01:56:53","slug":"%e5%80%bc%e5%be%97%e6%b7%b1%e6%80%9d%e7%9a%84php%e9%9d%a2%e8%af%95%e9%97%ae%e9%a2%98","status":"publish","type":"post","link":"http:\/\/www.homconnect.cn\/?p=124","title":{"rendered":"\u503c\u5f97\u6df1\u601d\u7684PHP\u9762\u8bd5\u95ee\u9898"},"content":{"rendered":"

 <\/p>\n

Q1<\/h3>\n

\u7b2c\u4e00\u4e2a\u95ee\u9898\u5173\u4e8e\u5f31\u7c7b\u578b<\/code><\/p>\n

$str1 = ‘yabadabadoo’;<\/em>
\n$str2 = ‘yaba’;<\/em>
\nif (strpos($str1,$str2)) { <\/em>
\n\u00a0 \u00a0 echo “\\”” . $str1 . “\\” contains \\”” . $str2 . “\\””;<\/em>
\n} else {<\/em>
\n\u00a0 \u00a0 echo “\\”” . $str1 . “\\” does not contain \\”” . $str2 . “\\””;<\/em>
\n}<\/em><\/p>\n

\u6b63\u786e\u8fd0\u884c\u7684\u8f93\u51fa\u7ed3\u679c:<\/p>\n

“yabadabadoo”<\/span> does not contain “yaba”<\/span><\/p>\n

strpos<\/code>\u662f\u8fd4\u56de\u5b57\u7b26\u4e32str2<\/code>\u5728str1<\/code>\u7684\u4f4d\u7f6e\uff0c\u6ca1\u6709\u627e\u5230\u5219\u8fd4\u56defalse<\/code>\u7136\u800c\u5b9e\u9645\u4e0a\u8fd9\u6b21\u8fd4\u56de\u4e860<\/code>\u800c\u5728if\u8bed\u53e5\u4e2d0\u4e5f\u88ab\u5f53\u4f5cfalse,\u6240\u4ee5\u6211\u4eec\u9700\u8981\u5bf9false\u505a\u7c7b\u578b\u5224\u65ad\uff0c\u6b63\u786e\u7684\u4ee3\u7801\u5982\u4e0b:<\/p>\n

$str1 = ‘yabadabadoo’;<\/em>
\n$str2 = ‘yaba’;<\/em>
\nif (strpos($str1,$str2) !== false) { <\/em>
\n\u00a0 \u00a0 echo “\\”” . $str1 . “\\” contains \\”” . $str2 . “\\””;<\/em>
\n} else {<\/em>
\n\u00a0 \u00a0 echo “\\”” . $str1 . “\\” does not contain \\”” . $str2 . “\\””;<\/em>
\n}<\/em><\/p>\n

\u9700\u8981\u6ce8\u610f\u7684\u662f\u6211\u4eec\u4f7f\u7528\u4e86!==<\/code>\uff0c\u5728php \u548c JS\u4e2d= !<\/mark>\u76f8\u5bf9== \u66f4\u4e3a\u4e25\u683c\u9700\u8981\u8981\u6c42\u6570\u636e\u7c7b\u578b\u4e00\u81f4\u3002<\/p>\n

<\/p>\n

Q2<\/h3>\n

\u4e0b\u9762\u7684\u8f93\u51fa\u7ed3\u679c\u4f1a\u662f\u600e\u6837\uff1f<\/p>\n

$x = 5;<\/em>
\necho $x; <\/em>
\necho “<br \/>”; <\/em>
\necho $x+++$x++; <\/em>
\necho “<br \/>”; <\/em>
\necho $x; <\/em>
\necho “<br \/>”; <\/em>
\necho $x—$x–; <\/em>
\necho “<br \/>”; <\/em>
\necho $x; <\/em><\/p>\n

\u5b9e\u9645\u8fd0\u884c\u7ed3\u679c\u662f<\/p>\n

5
\n11
\n7
\n1
\n5<\/p>\n

\u5173\u4e8e $x++<\/code> \u548c $x--<\/code>\u8fd9\u4e2a\u95ee\u9898\u5176\u5b9e\u975e\u5e38\u5bb9\u6613\u9047\u89c1\uff0c\u6211\u4eec\u53ea\u9700\u8bb0\u4f4f$x++<\/code>\u4f7f\u7528\u6700\u8fd1\u7684\u503c\uff0c\u7136\u540e\u624d\u81ea\u589e\u3002<\/p>\n

\u8fd0\u7b97\u7b26\u7684\u4f18\u5148\u7ea7\uff0c++<\/code> \u662f\u660e\u663e\u9ad8\u4e8e +<\/code>\uff0c\u56e0\u6b64\u5148\u6267\u884c++ \u518d\u6267\u884c + \u3002\u5173\u4e8e\u8fd0\u7b97\u7b26\u7684\u4f18\u5148\u7ea7\uff0c\u6709\u7684\u65f6\u5019\u6211\u4eec\u771f\u7684\u53ef\u4ee5\u901a\u8fc7\u62ec\u53f7\u6765\u8ba9\u6211\u4eec\u7684\u7a0b\u5e8f\u66f4\u8ba9\u4eba\u76f4\u89c2\u7684\u4e86\u89e3\uff0c\u6bd5\u7adf\u4ee3\u7801\u4e0d\u5149\u662f\u7528\u4e8e\u6267\u884c\u7684\uff0c\u6709\u7684\u65f6\u5019\u6216\u8bb8\u56e2\u961f\u7684\u53ef\u8bfb\u6027\u4e5f\u662f\u63d0\u9ad8\u6548\u7387\u7684\u4e00\u79cd\u3002<\/p>\n

Q3<\/h3>\n

\u5173\u4e8e\u53d8\u91cf\u7684\u5f15\u7528\uff1b<\/p>\n

$a = ‘1’;<\/em>
\n$b = &$a;<\/em>
\n$b = “2$b”;<\/em><\/p>\n

\u8bf7\u95ee $a<\/code> \u548c $b<\/code>\u7684\u503c\u5404\u4f4d\u591a\u5c11<\/p>\n

\u90e8\u5206\u7b2c\u4e00\u65f6\u95f4\u4f1a\u60f3\u5230 $a='1' $b='21'<\/code>,\u4ed4\u7ec6\u4e00\u770b $b=&$a<\/code>,\u8fd9\u91cc$b<\/code>\u662f\u53d8\u91cf$a<\/code>\u7684\u5f15\u7528\u800c\u4e0d\u662f\u76f4\u63a5 \u8d4b\u503c\u3002<\/p>\n

Q4<\/h4>\n

\u4e0b\u9762\u662ftrue\u8fd8\u662ffalse<\/p>\n

var_dump(0123 == 123);<\/em>
\nvar_dump(‘0123’ == 123);<\/em>
\nvar_dump(‘0123’ === 123);<\/em><\/p>\n

var_dump(0123 == 123);\/\/ false<\/code>,PHP\u4f1a\u9ed8\u8ba4\u628a0123\u5f53\u4f5c8\u8fdb\u5236\u6765\u5904\u7406\uff0c\u5b9e\u9645\u8f6c\u5316\u4e3a10\u8fdb\u5236\u5c31\u662f83\uff0c\u663e\u7136\u8fd9\u4e0d\u662f\u76f8\u7b49\u7684\u3002<\/p>\n

var_dump('0123' == 123);\/\/ true<\/code>\u8fd9\u91ccphp\u4f1a\u975e\u5e38\u6709\u8da3\u7684\u5c06’0123’\u8f6c\u6362\u6210\u4e00\u4e2a\u6570\u5b57\u800c\u4e14\u9ed8\u8ba4\u53bb\u6389\u4e86\u524d\u9762\u76840\u4e5f\u5c31\u662f123==123<\/code><\/p>\n

var_dump('0123' === 123);\/\/ false<\/code>\u5f88\u663e\u7136\u4e0a\u9762\u7684\u95ee\u9898\u5df2\u7ecf\u8bf4\u8fc7\u4e86\u6570\u5b57\u548c\u5b57\u7b26\u4e32\u7c7b\u578b\u4e0d\u4e00\u81f4\u3002<\/p>\n

Q5<\/h3>\n

\u4e0b\u9762\u7684\u4ee3\u7801\u6709\u4ec0\u4e48\u95ee\u9898\u5417\uff1f\u8f93\u51fa\u4f1a\u662f\u4ec0\u4e48\uff0c\u600e\u6837\u4fee\u590d\u5b83<\/p>\n

$referenceTable = array();<\/em>
\n$referenceTable[‘val1’] = array(1, 2);<\/em>
\n$referenceTable[‘val2’] = 3;<\/em>
\n$referenceTable[‘val3’] = array(4, 5);<\/em><\/p>\n

$testArray = array();<\/em><\/p>\n

$testArray = array_merge($testArray, $referenceTable[‘val1’]);<\/em>
\nvar_dump($testArray); <\/em>
\n$testArray = array_merge($testArray, $referenceTable[‘val2’]);<\/em>
\nvar_dump($testArray); <\/em>
\n$testArray = array_merge($testArray, $referenceTable[‘val3’]);<\/em>
\nvar_dump($testArray);<\/em><\/p>\n

\u5b9e\u9645\u8f93\u51fa\u5982\u4e0b\uff1a<\/p>\n

array(2) { [0]=> int(1) [1]=> int(2) }
\nNULL
\nNULL<\/p>\n

\u8fd0\u884c\u7684\u65f6\u5019\u4f60\u6216\u8bb8\u8fd8\u80fd\u770b\u5230\u4e0b\u9762\u7684\u8b66\u544a<\/p>\n

Warning: array_merge(): Argument #2 is not an array
\nWarning: array_merge(): Argument #1 is not an array<\/p>\n

array_merge<\/code>\u9700\u8981\u4f20\u5165\u7684\u53c2\u6570\u90fd\u662f\u6570\u7ec4\uff0c\u5982\u679c\u4e0d\u662f\uff0c\u5219\u4f1a\u8fd4\u56denull\u3002 \u4f60\u53ef\u4ee5\u8fd9\u6837\u4fee\u6539<\/p>\n

$testArray = array_merge($testArray, (array)$referenceTable[‘val1’]);<\/em>
\nvar_dump($testArray); <\/em>
\n$testArray = array_merge($testArray, (array)$referenceTable[‘val2’]);<\/em>
\nvar_dump($testArray); <\/em>
\n$testArray = array_merge($testArray, (array)$referenceTable[‘val3’]);<\/em>
\nvar_dump($testArray); <\/em><\/p>\n

Q6<\/h3>\n

$x\u5e94\u8be5\u662f\u8f93\u51fa\u4ec0\u4e48\uff1f<\/p>\n

$x = true and false;<\/em>
\nvar_dump($x);<\/em><\/p>\n

\u90e8\u5206\u540c\u5b66\u6216\u8bb8\u4f1a\u7b2c\u4e00\u65f6\u95f4\u60f3\u5230false,\u5b9e\u9645\u4e0a\u8fd9\u91cc\u4f9d\u65e7\u662f\u5f3a\u8c03\u8fd0\u7b97\u7b26\u7684\u4f18\u5148\u7ea7\uff0c\uff1d \u4f1a\u6bd4 and\u7ea7\u522b\u9ad8\u70b9\uff0c\u56e0\u6b64\u7b49\u540c\u4e0b\u9762\u7684\u4ee3\u7801<\/p>\n

$x = true<\/span>; <\/em><\/p>\n

true<\/span> and<\/span> false<\/span><\/p>\n

\u7b54\u6848\u663e\u800c\u6613\u89c1\u3002<\/p>\n

Q7<\/h3>\n

\u7ecf\u8fc7\u4e0b\u9762\u7684\u8fd0\u7b97 $x\u7684\u503c\u5e94\u8be5\u662f\u591a\u5c11\uff1f<\/p>\n

$x = 3<\/span> + “15%”<\/span> + “$25”<\/span><\/em><\/p>\n

Q8<\/h3>\n

\u8fd0\u884c\u4e0b\u9762\u7684\u4ee3\u7801\uff0c$text<\/code> \u7684\u503c\u662f\u591a\u5c11\uff1fstrlen($text)<\/code>\u53c8\u4f1a\u8fd4\u56de\u4ec0\u4e48\u7ed3\u679c\uff1f<\/p>\n

$text = ‘John ‘;<\/em>
\n$text[10] = ‘Doe’;<\/em><\/p>\n

\u4e0a\u9762\u4ee3\u7801\u6267\u884c\u5b8c\u6bd5\u540e $text = \"John D\"<\/code>(John\u540e\u9762\u4f1a\u6709\u8fde\u7eed\u76845\u4e2a\u7a7a\u683c) strlen($text)<\/code>\u4f1a\u8fd4\u56de11<\/p>\n

$text[10] = \"Doe\"<\/code>\u7ed9\u67d0\u4e2a\u5b57\u7b26\u4e32\u5177\u4f53\u7684\u67d0\u4e2a\u4f4d\u7f6e\u5177\u4f53\u5b57\u7b26\u65f6\u5019\uff0c\u5b9e\u9645\u53ea\u4f1a\u628aD\u8d4b\u7ed9$text<\/code>. \u867d\u7136$text<\/code>\u624d\u5f00\u59cb\u53ea\u67095\u4e2a\u81ea\u8d1f\u957f\u5ea6\uff0c\u4f46\u662fphp\u4f1a\u9ed8\u8ba4\u586b\u5145\u7a7a\u683c\u3002\u8fd9\u548c\u522b\u7684\u8bed\u8a00\u6709\u4e9b\u5dee\u522b\u3002<\/p>\n

Q9<\/h3>\n

\u4e0b\u9762\u7684\u8f93\u51fa\u7ed3\u679c\u4f1a\u662f\u4ec0\u4e48<\/p>\n

$v = 1;<\/em>
\n$m = 2;<\/em>
\n$l = 3;<\/em><\/p>\n

if( $l > $m > $v){ <\/em>
\n\u00a0 \u00a0 echo “yes”;<\/em>
\n}else{<\/em>
\n\u00a0 \u00a0 echo “no”;<\/em>
\n}<\/em><\/p>\n

\u5b9e\u9645\u7684\u8f93\u51fa\u662f”no”,\u53ea\u8981\u4ed4\u7ec6\u5206\u6790\u5c31\u4e0d\u96be\u5f97\u51fa<\/p>\n

$l>$m<\/code> \u4f1a\u8f6c\u6362\u62101 \uff0c\u5219\u8fd9\u4e2a\u65f6\u5019\u518d\u548c$m\u6bd4\u8f83\u3002<\/p>\n

Q10<\/h3>\n

\u6267\u884c\u4e0b\u9762\u4ee3\u7801$x<\/code>\u4f1a\u53d8\u6210\u4ec0\u4e48\u503c\u5462\uff1f<\/p>\n

$x = NULL;<\/em><\/p>\n

if (‘0xFF’ == 255) { <\/em>
\n\u00a0 \u00a0 $x = (int)’0xFF’;<\/em>
\n}<\/em><\/p>\n

\u5b9e\u9645\u7684\u8fd0\u884c\u7ed3\u679c\u662f$x=0<\/code>\u800c\u4e0d\u662f255.<\/p>\n

\u9996\u5148'oxFF' == 255<\/code>\u6211\u4eec\u597d\u5224\u65ad\uff0c\u4f1a\u8fdb\u884c\u8f6c\u6362\u5c0616\u8fdb\u5236\u6570\u5b57\u8f6c\u6362\u621010\u8fdb\u5236\u6570\u5b57\uff0c0xff -> 255.<\/p>\n

PHP\u4f7f\u7528is_numeric_string<\/code> \u5224\u65ad\u5b57\u7b26\u4e32\u662f\u5426\u5305\u542b\u5341\u516d\u8fdb\u5236\u6570\u5b57\u7136\u540e\u8fdb\u884c\u8f6c\u6362\u3002<\/p>\n

\u4f46\u662f$x = (int)'0xFF';<\/code>\u662f\u5426\u4e5f\u4f1a\u53d8\u6210255\u5462\uff1f\u663e\u7136\u4e0d\u662f\uff0c\u5c06\u4e00\u4e2a\u5b57\u7b26\u4e32\u8fdb\u884c\u5f3a\u5236\u7c7b\u578b\u8f6c\u6362\u5b9e\u9645\u4e0a\u7528\u7684\u662fconvert_to_long<\/code>,\u5b83\u5b9e\u9645\u4e0a\u662f\u5c06\u5b57\u7b26\u4e32\u4ece\u5de6\u5411\u53f3\u8fdb\u884c\u8f6c\u6362\uff0c\u9047\u5230\u975e\u6570\u5b57\u5b57\u7b26\u5219\u505c\u6b62\u3002\u56e0\u6b640xFF<\/code>\u5230x\u5c31\u505c\u6b62\u4e86\u3002\u6240\u4ee5$x=0<\/code><\/p>\n

 <\/p>\n

\u539f\u6587\u94fe\u63a5\uff1ahttp:\/\/www.jackpu.com\/-10ge-zhi-de-shen-si-de-phpmian-shi-wen-ti\/<\/p>\n","protected":false},"excerpt":{"rendered":"

  Q1 \u7b2c\u4e00\u4e2a\u95ee\u9898\u5173\u4e8e\u5f31\u7c7b\u578b $str1 = ‘yabadabadoo’; … \u7ee7\u7eed\u9605\u8bfb\u201c\u503c\u5f97\u6df1\u601d\u7684PHP\u9762\u8bd5\u95ee\u9898\u201d<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[3],"tags":[],"_links":{"self":[{"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=\/wp\/v2\/posts\/124"}],"collection":[{"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=124"}],"version-history":[{"count":1,"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=\/wp\/v2\/posts\/124\/revisions"}],"predecessor-version":[{"id":125,"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=\/wp\/v2\/posts\/124\/revisions\/125"}],"wp:attachment":[{"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=124"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=124"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.homconnect.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=124"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}