{"id":202,"date":"2010-09-07T16:50:13","date_gmt":"2010-09-07T08:50:13","guid":{"rendered":"http:\/\/www.qyuef.com\/?p=202"},"modified":"2010-09-07T16:50:13","modified_gmt":"2010-09-07T08:50:13","slug":"php%e4%b8%ad%e6%96%87%e5%ad%97%e7%ac%a6%e4%b8%b2%e6%88%aa%e5%8f%96%e5%87%bd%e6%95%b0","status":"publish","type":"post","link":"http:\/\/www.qyuef.com\/?p=202","title":{"rendered":"php\u4e2d\u6587\u5b57\u7b26\u4e32\u622a\u53d6\u51fd\u6570"},"content":{"rendered":"<pre lang=\"php\" line=\"1\">\nfunction left($str, $len, $charset=\"utf-8\")\n{\n if( !is_numeric($len) or $len < = 0)\/\/\u5982\u679c\u622a\u53d6\u957f\u5ea6\u5c0f\u4e8e\u7b49\u4e8e\n {\n  return \"\";      \/\/\u8fd4\u56de\u7a7a\n }\n $sLen = strlen($str);    \/\/\u83b7\u53d6\u539f\u59cb\u5b57\u4e32\u957f\u5ea6\n if( $len >= $sLen )     \/\/\u5982\u679c\u622a\u53d6\u957f\u5ea6\u5927\u4e8e\u603b\u5b57\u7b26\u4e32\u957f\u5ea6\n {\n  return $str;     \/\/\u76f4\u63a5\u8fd4\u56de\u5f53\u524d\u5b57\u7b26\u4e32\n } \n if ( strtolower($charset) == \"utf-8\" ) \/\/\u5982\u679c\u7f16\u7801\u4e3a\u4e3autf-8\n {\n  $len_step = 3;      \/\/\u5219\u4e2d\u6587\u5b57\u7b26\u957f\u5ea6\u4e3a3\n }\n else         \/\/\u5982\u679c\u4e0d\u662f\n {\n  $len_step = 2;      \/\/\u5982\u679c\u662fgb2312\u6216big5\u7f16\u7801\uff0c\u5219\u4e2d\u6587\u5b57\u7b26\u957f\u5ea6\u4e3a2\n }\n \/\/\u6267\u884c\u622a\u53d6\u64cd\u4f5c\n $len_i = 0;   \/\/\u521d\u59cb\u5316\u8ba1\u6570\u5f53\u524d\u5df2\u622a\u53d6\u7684\u5b57\u7b26\u4e32\u4e2a\u6570\uff0c\u6b64\u503c\u4e3a\u5b57\u7b26\u4e32\u7684\u4e2a\u6570\u503c\n $substr_len = 0; \/\/\u521d\u59cb\u5316\u5e94\u8be5\u8981\u622a\u53d6\u7684\u603b\u5b57\u8282\u6570\n for( $i=0; $i < $sLen; $i++ )  \/\/\u5f00\u59cb\u5faa\u73af\n {\n  if ( $len_i >= $len ) break; \/\/\u603b\u622a\u53d6$len\u4e2a\u5b57\u7b26\u4e32\u540e\uff0c\u505c\u6b62\u5faa\u73af\n  if( ord(substr($str,$i,1)) > 0xa0 ) \/\/\u5982\u679c\u662f\u4e2d\u6587\u5b57\u7b26\u4e32\n  {\n   $i += $len_step - 1;   \/\/\n   $substr_len += $len_step;  \/\/\u5f53\u524d\u603b\u5b57\u8282\u6570\u52a0\u4e0a\u76f8\u5e94\u7f16\u7801\u7684\u4e2d\u6587\u5b57\u7b26\u957f\u5ea6\n  }\n  else        \/\/\u5982\u679c\u5b57\u7b26\u4e0d\u662f\u4e2d\u6587\n  {\n   $substr_len ++;     \/\/\u52a01\u4e2a\u5b57\u8282\n  }\n  $len_i ++;     \/\/\u5df2\u7ecf\u622a\u53d6\u5b57\u7b26\u4e32\u4e2a\u6570\u589e\u52a0\n }\n $result_str = substr($str,0,$substr_len ); \/\/\u83b7\u53d6\u7ed3\u679c\n return $result_str;    \/\/\u8fd4\u56de\u7ed3\u679c\n}\n\n\n<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>\u5728php\u7f51\u7ad9\u5f00\u53d1\u8fc7\u7a0b\u4e2d\uff0c\u5bf9\u4e8e\u5b57\u7b26\u4e32\u7684\u622a\u53d6\u662f\u5fc5\u4e0d\u53ef\u5c11\u7684\u3002\u6bcf\u4e2a\u4eba\u90fd\u6709\u81ea\u5df1\u4e0d\u540c\u7684\u65b9\u6cd5\u3002\u8fd9\u91cc\u6211\u5c06\u5206\u4eab\u4e00\u4e0b\u6211\u6240\u4f7f\u7528\u7684\u5b57\u7b26\u4e32\u622a\u53d6\u51fd\u6570\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[8],"tags":[26,75],"tcat":[],"_links":{"self":[{"href":"http:\/\/www.qyuef.com\/index.php?rest_route=\/wp\/v2\/posts\/202"}],"collection":[{"href":"http:\/\/www.qyuef.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.qyuef.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.qyuef.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.qyuef.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=202"}],"version-history":[{"count":0,"href":"http:\/\/www.qyuef.com\/index.php?rest_route=\/wp\/v2\/posts\/202\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.qyuef.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=202"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.qyuef.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=202"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.qyuef.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=202"},{"taxonomy":"tcat","embeddable":true,"href":"http:\/\/www.qyuef.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftcat&post=202"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}