變更變數值

可以變更值:

• 至常數，如下列範例所示:

  
  CHGVAR   VAR(&INVCMPLT)   VALUE(0)
  

  &INVCMPLT is set to 0.

  您也可以使用此表示法:

  
  CHGVAR   &INVCMPLT  0
  

• 變更為另一個變數的值，如下列範例所示:

  
  CHGVAR   VAR(&A)   VALUE(&B)
  

  &A is set to the value of the variable &B

  您也可以使用此表示法:

  
  CHGVAR   &A  &B
  

• 評估表示式之後的表示式值，如下列範例所示:

  
  CHGVAR   VAR(&A)   VALUE(&A + 1)
  

  The value of &A is increased by 1.

  您也可以使用此表示法:

  
  CHGVAR   &A  (&A + 1)
  

• 至內建函數 %SST 所產生的值，如下列範例所示:

  
  CHGVAR   VAR(&A)   VALUE(%SST(&B 1 5))
  

  &A is set to the first five characters of the value of the variable &B

• 至內建函數 %SWITCH 所產生的值，如下列範例所示:

  
  CHGVAR  VAR(&A)  VALUE(%SWITCH(0XX111X0))
  

  &A is set to 1 if job switches 1 and 8 are 0 and job switches 4, 5 and 6 are 1; otherwise, &A is set to 0.

• 至內建函數 %BIN 所產生的值:

  
  CHGVAR  VAR(&A)  VALUE(%BIN(&B 1 4))
  

  The first four characters of variable &B are converted to the decimal equivalent and stored in variable &A.

• 至內建函數 %CHECK 所產生的值:

  CHGVAR  VAR(&A)  VALUE(%CHECK('0123456789' &B))

  The value in variable &B is checked and the position of the leftmost character that is not a digit is stored in variable &A. If all the characters in variable &B are digits, a value of zero is stored in variable &A.

• 至內建函數 %CHECKR 所產生的值:

  CHGVAR  VAR(&A)  VALUE(%CHECKR('*' &B))

  The value in variable &B is checked and the position of the rightmost character that is not an asterisk (*) is stored in variable &A. If all the characters in variable &B are asterisks, a value of zero is stored in variable &A.

• 至內建函數 %SCAN 所產生的值:

  
  CHGVAR  VAR(&A)  VALUE(%SCAN('.' &B))
  

  The value in variable &B is scanned and the position of the leftmost period (.) character is stored in variable &A. If there are no period characters in variable &B, a value of zero is stored in variable &A.

• 至內建函數 %TRIM 所產生的值:

  CHGVAR  VAR(&A)  VALUE(%TRIM(&B '* '))

  Leading and trailing asterisk (*) and blank characters in variable &B will be trimmed off and the resulting string will be stored in variable &A.

• 至內建函數 %TRIML 所產生的值:

  
  CHGVAR  VAR(&A)  VALUE(%TRIML(&B))
  

  Leading blank characters in variable &B will be trimmed off and the resulting string will be stored in variable &A.

• 至內建函數 %TRIMR 所產生的值:

  
  CHGVAR  VAR(&A)  VALUE(%TRIMR(&B '*'))
  

  Trailing asterisk (*) characters in variable &B will be trimmed off and the resulting string will be stored in variable &A.

• 至內建函數 %CHAR 所產生的值:

  
  CHGVAR  VAR(&A)  VALUE(%CHAR(&B))
  

  Variable &B will be converted into character format and the resulting string will be stored in variable &A.

• 至內建函數 %UPER 所產生的值:

  
  CHGVAR  VAR(&A)  VALUE(%UPPER(&B))
  

  Lowercase letters in variable &B will be converted into uppercase letters and the resulting string will be stored in variable &A.

• 至內建函數 %SIZE 所產生的值:

  
  CHGVAR  VAR(&A)  VALUE(%SIZE(&B))
  

  The number of bytes occupied by variable &B will be stored in variable &A.

• 至內建函數 %PARMS 所產生的值:

  CHGVAR  VAR(&A)  VALUE(%PARMS())
  

  The number of parameters that were passed to the program will be stored in variable &A.

CHGVAR 指令可用來擷取及變更區域資料區。 例如，下列指令會清空本端資料區的 10 個位元組，並擷取部分本端資料區:

CHGVAR %SST(*LDA 1 10) ' '
 
CHGVAR &A %SST(*LDA 1 10)

下表顯示從值 (文字或變數) 到變數的有效指派。