PHP中奇怪的數字 – 馬永占 譯

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原文地址：http://phplens.com/phpeverywhere/?q=node/view/249
由一條別人adodb的bug引發的思考
 
echo 09," => (09) <br>";
echo 9," => (9) <br>";
 
你可以試一下.輸出結果是:
 
0 => (09)

9 => (9)
 
而不是
 
09 => (09)

9 => (9)
 
 
 
 
 
這個譯者做了下測試,經過分析得出.0開頭的數字會被當成8進位,0x開頭的會被當成16進位,如下:
 
echo 0x11," => (011) <br>";

echo 010," => (010) <br>";
 
這個會輸出:
 
17 => (011)

8 => (010)
 
當然是10x16+1=17
 
1x8+0=8
 
OK.
 
 
 
 
 
 
 
 
 
Someone reported a bug in ADOdb, the open source db library i maintain. I went crazy for half an hour until i realised the problem. Here's a little gotcha you can try:
echo 09," => (09) <br>";
echo 9," => (9) <br>";
If you expect the above code to produce the same values, you are sadly mistaken. Try it. I will post a followup later