REXX - 从CSV文件解析

问题描述：

我在解析文本文件中的CSV时遇到问题，并想知道您是否可以帮助我。到目前为止，我有以下内容：REXX - 从CSV文件解析

CSV文件（DATA.txt）看起来像这样，它总是会有15个字段全部用逗号分隔。并非所有字段都是强制性的，所以有些字段会被填充，有些字段是空白的

Seattle,Lastname,Firstname,DOB,SEX,etc,etc 
Seattle,Lastname,Firstname,DOB,,etc,etc 
Portland,Lastname,Firstname,DOB,SEX,,,etc 
Portland,Lastname,Firstname,DOB,SEX,etc,etc

这里是我的REXX代码

SOURCEFILE = "C:\DATA\DATA.TXT" 
IF A=2 THEN DO COUNTER=1 TO LINES(SOURCEFILE) 
    PARSE VALUE LINEIN(SOURCEFILE) WITH CITY "," LAST_NAME "," FIRST_NAME "," MOM_NAME "," MIDDLE_NAME "," DAD_NAME "," DOB "," etc "," etc "," etc "," etc "," SEX "," etc "," etc 
    CALL SETCURSOR 4,23 
    CALL CREATEDATA 
END 

CREATEDATA: 
CALL TYPE CITY 
CALL PRESS TAB 
CALL TYPE LAST_NAME 
CALL PRESS TAB 
CALL TYPE DATE(U) 
CALL PRESS TAB 
CALL TYPE FIRST_NAME 
CALL PRESS TAB 
CALL PRESS ENTER 
RETURN

我不知道我是否应该在解析时使用ARG或VAR或者，如果我写了正确的前两行。事实上，我知道我的CREATEDATA函数正常工作，因为我得到了输入的“CITY”而不是解析值。任何帮助将非常感激。谢谢！

答

几点意见：

1）Lines(SourceFile) Windows系统可能包括读取整个文件上计算CR-LF序列。然后你的Parse value LineIn(SourceFile)循环再次读取它。典型的Rexx的方式做，这将是：

Address SYSTEM 'TYPE' SourceFile with output stem Lines. 
Do Counter = 1 to Lines.0 
    Parse var Lines.Counter ... 
End 
Drop Lines.

至少，只要该文件不是太大，保持它在阵列中存储成本。

2）您在循环结束时流入CreateData，这就是您看到“CITY”的原因。在End之后，您需要一个Return或Exit指令。

3）根据＃2，显然Parse从未被执行，因为City未初始化（Rexx中的未初始化变量的值是大写的名称）。它的条件是A=2，但情况并非如此。

根据Cowlishaw的Rexx的书，建在函数中的行可能返回的行数中引用的文件或，如果不能确定，“1”，其中一个非零计数将适当，否则为'0'。我在窗口上使用ooRexx相当多，可以确认ooRexx不计算所有行，它只返回0/1。我使用以下命令一次读取一行文件：DO WHILE LINES（filename）> 0; PARSE VALUE LINEIN（文件名）与...; END – NealB 2013-04-12 13:38:18

“Lines（）”的结果与实现有关。有些实现会返回一个计数，其他实例只会返回1或0。这也是为什么我更喜欢加载词干：'Lines.0'是一个实际的计数。 – 2013-04-12 23:33:01

答

一个问题是什么，如果A = 2，那么在

IF A=2 THEN DO COUNTER=1 TO LINES(SOURCEFILE)

如果A宗旨！= 2的循环被旁路。我怀疑你的程序应该是：

SOURCEFILE = "C:\DATA\DATA.TXT" 
DO COUNTER=1 TO LINES(SOURCEFILE) 
    PARSE VALUE LINEIN(SOURCEFILE) WITH CITY "," LAST_NAME "," FIRST_NAME "," MOM_NAME "," MIDDLE_NAME "," DAD_NAME "," DOB "," etc "," etc "," etc "," etc "," SEX "," etc "," etc 
    CALL SETCURSOR 4,23 
    CALL CREATEDATA 
END 

RETURN /* prevent the fall through to createdata */ 

CREATEDATA: 




---------------------------

解析的语句具有以下基本格式

解析[来源] [解析控制]

其中[来源] icludes

ARG - 过程调用参数拉 - 数据从堆栈中取出 var - 数据来自变量值...提供数据在线

所以你的解析也能像

linein = LINEIN(SOURCEFILE) 
    PARSE var linein CITY "," LAST_NAME "," FIRST_NAME "," MOM_NAME "," MIDDLE_NAME "," DAD_NAME "," DOB "," etc "," etc "," etc "," etc "," SEX "," etc "," etc

或

做

DO COUNTER=1 TO LINES(SOURCEFILE) 
     CALL SETCURSOR 4,23 
     CALL CREATEDATA LINEIN(SOURCEFILE) 
    END 

    RETURN /* prevent the fall through to createdata */ 

    CREATEDATA: 
    parse arg CITY "," LAST_NAME "," FIRST_NAME "," MOM_NAME "," MIDDLE_NAME "," DAD_NAME "," DOB "," etc "," etc "," etc "," etc "," SEX "," etc "," etc

最后屁股罗斯说你应该尝试aviod线（的资源文件），因为它涉及到整个文件读

REXX - 从CSV文件解析

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