2013-02-27 129 views
0

我没有使用Visual FoxPro一段时间。今天,我的前同事问我如何从名称字段中删除非字符,即只允许a-z和A-Z。我记得我使用了一个名为strstran的函数来完成它。我需要定义一个包含a-z和A-Z的变量。但我现在不记得了。有人知道如何处理这个问题。提前致谢。如何使用visual foxpro从名称字段中删除非字符字母

回答

5

使用CHRTRAN()函数。

FUNCTION GetAlphaCharacters 
    LPARAMETERS tcExpressionSearched 

    LOCAL lcAllowedCharacters 
    m.lcAllowedCharacters = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" 

    RETURN CHRTRAN(m.tcExpressionSearched, CHRTRAN(m.tcExpressionSearched, m.lcAllowedCharacters, ""), "") 
ENDFUNC 
0

另一种选择是使用ISALPHA()。这只会查看字符串中最左边的位置,但不区分大小写。

***This should work, but I haven't tested it. 
myresults = "" 
myvar = "MyText12" 
FOR(i = 1 TO LEN(myvar)) 
    IF ISALPHA(SUBSTR(myvar, i, 1)) 
    myresults = myresults + SUBSTR(myvar, i, 1) 
    ENDIF 
ENDFOR 
RETURN myresults 
0

我知道我对晚会有点迟,但这是我写的一个函数,用于清除字符串中所有不可打印的ASCII字符。

CLEAR 

    * Contains ASCII characters 1 (SOH) and 2 (STX) 
    cTest = "Garbage Data "  

    ? cTest 
    cTest = RemoveNonPrintableCharacters(cTest) 
    ? cTest 


    FUNCTION RemoveNonPrintableCharacters 
     LPARAMETERS tcExpressionSearched 

     cCleanExpression = tcExpressionSearched 

     * Cleans out the first 32 ASCII characters, which are not printable 
     FOR decCount = 0 TO 31 
      cCleanExpression = CHRTRAN(m.cCleanExpression, CHR(decCount), "")  
     ENDFOR 

     * Also cleans out the non-printable DEL character (ASCII 127) 
     cCleanExpression = CHRTRAN(m.cCleanExpression, CHR(127), "") 

     * Return the clean string 
     RETURN cCleanExpression 
    ENDFUNC 
相关问题