setleng();
定义上限
Sets the length of a string or dynamic-array variable.
Unit
System
Category
string handling routines
procedure SetLength(var S
NewLength: Integer);
Description
S is a string or dynamic-array variable.
For a short-string variable, SetLength simply sets the length-indicator character (the character at S[0]) to the given value. In this case, NewLength must be a value between 0 and 255.
For a long-string or dynamic-array variable, SetLength reallocates the string or array referenced by S to the given length. Existing characters in the string or elements in the array are preserved, but the content of newly allocated space is undefined. If there is not enough memory available to reallocate the variable, an EOutOfMemory exception is raised. Following a call to SetLength, S is guaranteed to reference a unique string or array梩hat is a string or array with a reference count of one.
