sys(16,1)?

[shellyang]

请解释一下什么意思?

[river_sea]

没有用过，以下说明给你参考。

SYS(16) - Executing Program File Name

Returns the file name of the program being executed.

Syntax

SYS(16 [, nProgramLevel])

Returns

Character

Arguments

nProgramLevel

Indicates from how many levels back the program name is fetched. This value can range from 1 to the depth at which programs are nested.

If nProgramLevel is 0 or 1, SYS(16) returns the name of the main program (the program first executed). The name of the currently executing program is returned if nProgramLevel is omitted. The empty string is returned if nProgramLevel is greater than the program nesting depth.

Remarks

This option is useful for recovering from errors. SYS(16) is similar to PROGRAM( ). However, SYS(16) returns a path with the program name; whereas PROGRAM( ) returns just the program name.

If a procedure or function is being executed, SYS(16) returns the name of the file containing the procedure or function after the procedure or function name.

When the executing program is part of an application (.app), SYS(16) returns only the name of the program — the path isn't returned with the program name.

[winjet]

sys(16) - 正在执行的程序文件名

返回正在执行的程序文件名。

语法

SYS(16 [, nProgramLevel])

返回值类型

字符型

参数
nProgramLevel

指示从第几层嵌套中获取程序名。该值范围可以 1 变化到程序嵌套的层数。
如果 nProgramLevel 是 0 或 1，SYS(16) 返回主程序名(第一个执行的程序)；如果省略了 nProgramlevel 参数，那么返回当前正在执行的程序名；如果 nProgramlevel 参数大于程序嵌套深度，则返回一个空串。

说明

如果要从错误中恢复过来，该函数很有用。SYS(16) 与 PROGRAM( ) 相似，然而，SYS(16) 返回带路径的程序名，而 PROGRAM( ) 只返回程序名。
如果正在执行一个过程或函数，SYS(16) 在过程或函数名之后返回包含该过程或函数的文件名。
当正在执行的程序是应用程序 (.APP) 的一部分，那么 SYS(16) 只返回程序名(路径不和程序名一起返回)。

[shellyang]

a=sys(16,1)
?a
b=at(":",a)-1
?b
c=rat("\",a)-b
?c
d=substr(a,b,c)
?d
set default to substr(a,b,c)