再介绍一种使用指令”Strg_TO_Chars+SPLIT“的实现方法，用的variant比较多，适用于读取字符串中的多个子字符串，如楼主的问题，直接分解成4个子字符串，只需要输出第3个子字符串即可；缺点就是占用DB空间比较多。

代码如下，

//////////////////////////////////////////////////////////

//String-->arrayChars-->split

REGION initialization

    #tempStr_source := #iStr_source;

    #tempInt_moveResult1 := MOVE_BLK_VARIANT(SRC := #iVar_emptyChars, COUNT := #cUDInt_stringMax, SRC_INDEX := #cDInt_zero, DEST_INDEX := #cDInt_zero, DEST => #ioArr_chars);//clear buffer

    #tempInt_sourceLength := LEN(#tempStr_source);

END_REGION

REGION logic

    Strg_TO_Chars(Strg := #tempStr_source,

                  pChars := #cDInt_zero,

                  Cnt => #tempInt_sourceLength,

                  Chars := #ioArr_chars);

    #oInt_splitResult := SPLIT(Mode := #iDW_mode, RecSeparator := #iVar_recSeparator, EndSeparator := #iVar_endSeparator, SrcArray := #ioArr_chars, Count => #oUdint_count, DstStruct := #ioArr_desStruct, Position := #statUdint_position);

    #tempInt_moveResult2 := MOVE_BLK_VARIANT(SRC := #ioArr_desStruct, COUNT := #cUDInt_one, SRC_INDEX := #cDInt_two, DEST_INDEX := #cDInt_zero, DEST => #tempStr_substring);//copy the third split string to temp 

    #statUdint_position := #cUDInt_zero;//clear position value otherwise it will not work again when source string has changed

END_REGION

REGION output

    #oStr_substring := #tempStr_substring;

END_REGION