php 2007-11-5 09:58
注意php开发中的细节，寻找优化思路
[color=#000000][color=#0000cc]<[/color][color=#0000cc]?[/color][color=#0000ff]php[/color]
[color=#ff9900]// == 与 ===
[/color]
[color=#0000ff]$[/color][color=#008080]a[/color] [color=#0000cc]=[/color] 0[color=#0000cc];[/color]
[color=#0000ff]$[/color][color=#008080]b[/color] [color=#0000cc]=[/color] [color=#0000ff]NULL[/color][color=#0000cc];[/color]
[color=#0000ff]if[/color] [color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]a[/color] [color=#0000cc]=[/color][color=#0000cc]=[/color] [color=#0000ff]$[/color][color=#008080]b[/color][color=#0000cc])[/color] [color=#0000cc]{[/color]
[color=#ff9900]//return true;
[/color]
[color=#ff0000]print[/color] [color=#0000cc]([/color][color=#ff00ff]"true!"[/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#0000ff]else[/color] [color=#0000cc]{[/color]
[color=#ff9900]//return false;
[/color]
[color=#ff0000]print[/color] [color=#0000cc]([/color][color=#ff00ff]"wrong"[/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#ff0000]echo[/color] [color=#ff00ff]"<br />"[/color][color=#0000cc];[/color]
[color=#ff9900]// empty 与 is_null
[/color]
[color=#0000ff]$[/color][color=#008080]str[/color] [color=#0000cc]=[/color] [color=#ff00ff]""[/color][color=#0000cc];[/color]
[color=#0000ff]if[/color] [color=#0000cc]([/color][color=#ff0000]empty[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]str[/color][color=#0000cc])[/color] [color=#0000cc])[/color] [color=#0000cc]{[/color]
[color=#ff0000]echo[/color] [color=#ff00ff]"true"[/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#0000ff]else[/color] [color=#0000cc]{[/color]
[color=#ff0000]echo[/color] [color=#ff00ff]"not true"[/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#ff0000]echo[/color] [color=#ff00ff]"<br />"[/color][color=#0000cc];[/color]
[color=#0000ff]if[/color][color=#0000cc]([/color][color=#ff0000]is_null[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]str[/color][color=#0000cc])[/color][color=#0000cc])[/color] [color=#0000cc]{[/color]
[color=#ff0000]echo[/color] [color=#ff00ff]"Null"[/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#0000ff]else[/color] [color=#0000cc]{[/color]
[color=#ff0000]echo[/color] [color=#ff00ff]"NOT NULL"[/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#ff9900]// for while 与 foreach
[/color]
[color=#0000ff]$[/color][color=#008080]arr[/color] [color=#0000cc]=[/color] [color=#ff0000]array[/color][color=#0000cc]([/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000ff]for[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]i[/color] [color=#0000cc]=[/color] 0[color=#0000cc];[/color] [color=#0000ff]$[/color][color=#008080]i[/color] [color=#0000cc]<[/color] 50000[color=#0000cc];[/color] [color=#0000ff]$[/color][color=#008080]i[/color][color=#0000cc]+[/color][color=#0000cc]+[/color][color=#0000cc])[/color][color=#0000cc]{[/color]
[color=#0000ff]$[/color][color=#008080]arr[/color][color=#0000cc][[/color][color=#0000cc]][/color] [color=#0000cc]=[/color] [color=#0000ff]$[/color][color=#008080]i[/color][color=#0000cc]*[/color][color=#ff0000]rand[/color][color=#0000cc]([/color]1000[color=#0000cc],[/color]9999[color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#0000ff]function[/color] GetRunTime[color=#0000cc]([/color][color=#0000cc])[/color]
[color=#0000cc]{[/color]
[color=#ff0000]list[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]usec[/color][color=#0000cc],[/color][color=#0000ff]$[/color][color=#008080]sec[/color][color=#0000cc])[/color][color=#0000cc]=[/color][color=#ff0000]explode[/color][color=#0000cc]([/color][color=#ff00ff]" "[/color][color=#0000cc],[/color][color=#ff0000]microtime[/color][color=#0000cc]([/color][color=#0000cc])[/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000ff]return[/color] [color=#0000cc]([/color][color=#0000cc]([/color]float[color=#0000cc])[/color][color=#0000ff]$[/color][color=#008080]usec[/color][color=#0000cc]+[/color][color=#0000cc]([/color]float[color=#0000cc])[/color][color=#0000ff]$[/color][color=#008080]sec[/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#0000ff]$[/color][color=#008080]time_start[/color] [color=#0000cc]=[/color] GetRunTime[color=#0000cc]([/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000ff]for[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]i[/color] [color=#0000cc]=[/color] 0[color=#0000cc];[/color] [color=#0000ff]$[/color][color=#008080]i[/color] [color=#0000cc]<[/color] [color=#ff0000]count[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]arr[/color][color=#0000cc])[/color][color=#0000cc];[/color] [color=#0000ff]$[/color][color=#008080]i[/color][color=#0000cc]+[/color][color=#0000cc]+[/color][color=#0000cc])[/color][color=#0000cc]{[/color]
[color=#0000ff]$[/color][color=#008080]str[/color] [color=#0000cc].[/color][color=#0000cc]=[/color] [color=#0000ff]$[/color][color=#008080]arr[/color][color=#0000cc][[/color][color=#0000ff]$[/color][color=#008080]i[/color][color=#0000cc]][/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#0000ff]$[/color][color=#008080]time_end[/color] [color=#0000cc]=[/color] GetRunTime[color=#0000cc]([/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000ff]$[/color][color=#008080]time_used[/color] [color=#0000cc]=[/color] [color=#0000ff]$[/color][color=#008080]time_end[/color] [color=#0000cc]-[/color] [color=#0000ff]$[/color][color=#008080]time_start[/color][color=#0000cc];[/color]
[color=#ff0000]echo[/color] [color=#ff00ff]'For:'[/color][color=#0000cc].[/color][color=#ff0000]round[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]time_used[/color][color=#0000cc],[/color] 7[color=#0000cc])[/color][color=#0000cc].[/color][color=#ff00ff]'(s)<br><br>'[/color][color=#0000cc];[/color]
[color=#ff0000]unset[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]str[/color][color=#0000cc],[/color] [color=#0000ff]$[/color][color=#008080]time_start[/color][color=#0000cc],[/color] [color=#0000ff]$[/color][color=#008080]time_end[/color][color=#0000cc],[/color] [color=#0000ff]$[/color][color=#008080]time_used[/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000ff]$[/color][color=#008080]time_start[/color] [color=#0000cc]=[/color] GetRunTime[color=#0000cc]([/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000ff]while[/color][color=#0000cc]([/color][color=#ff0000]list[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]key[/color][color=#0000cc],[/color] [color=#0000ff]$[/color][color=#008080]val[/color][color=#0000cc])[/color] [color=#0000cc]=[/color] [color=#ff0000]each[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]arr[/color][color=#0000cc])[/color][color=#0000cc])[/color][color=#0000cc]{[/color]
[color=#0000ff]$[/color][color=#008080]str[/color] [color=#0000cc].[/color][color=#0000cc]=[/color] [color=#0000ff]$[/color][color=#008080]val[/color][color=#0000cc];[/color]
[color=#0000cc]}[/color]
[color=#0000ff]$[/color][color=#008080]time_end[/color] [color=#0000cc]=[/color] GetRunTime[color=#0000cc]([/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000ff]$[/color][color=#008080]time_used[/color] [color=#0000cc]=[/color] [color=#0000ff]$[/color][color=#008080]time_end[/color] [color=#0000cc]-[/color] [color=#0000ff]$[/color][color=#008080]time_start[/color][color=#0000cc];[/color]
[color=#ff0000]echo[/color] [color=#ff00ff]'While:'[/color][color=#0000cc].[/color][color=#ff0000]round[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]time_used[/color][color=#0000cc],[/color] 7[color=#0000cc])[/color][color=#0000cc].[/color][color=#ff00ff]'(s)<br><br>'[/color][color=#0000cc];[/color]
[color=#ff0000]unset[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]str[/color][color=#0000cc],[/color] [color=#0000ff]$[/color][color=#008080]key[/color][color=#0000cc],[/color] [color=#0000ff]$[/color][color=#008080]val[/color][color=#0000cc],[/color] [color=#0000ff]$[/color][color=#008080]time_start[/color][color=#0000cc],[/color] [color=#0000ff]$[/color][color=#008080]time_end[/color][color=#0000cc],[/color] [color=#0000ff]$[/color][color=#008080]time_used[/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000ff]$[/color][color=#008080]time_start[/color] [color=#0000cc]=[/color] GetRunTime[color=#0000cc]([/color][color=#0000cc])[/color][color=#0000cc];[/color]
[color=#0000ff]foreach[/color][color=#0000cc]([/color][color=#0000ff]$[/color][color=#008080]arr[/color] [color=#0000ff]as[/color] [color=#0000ff]$[/color][color=#008080]key[/color] [color=#0000cc]=[/color][color=#0000cc]>[/color] [color=#0000ff]$[/color][color=#008080]val[/color][color=#0000cc])[/color][color=#0000cc]{[/color]
[color=#0000ff]$[/color][color=#008080]str[/color] [color=#0000cc].[/color][color=#0000cc]=[/color] [color=#0000ff]$[/color][color=#008080]val[/color][color=#0000cc];[/color]
[color=#0000cc]?[/color][color=#0000cc]>[/color][/color]