如何删除字符串中某个字符后的所有内容？

Question

如何在＆＃39;？＆＃39;之后删除字符串中的所有内容？ ？到目前为止我的代码搜索了＆＃39;？＆＃39;。我该如何从那里开始？

这是我的代码。

INCLUDE Irvine32.inc

.data
source BYTE "Is this a string? Enter y for yes, and n for no",0

.code
main PROC

mov edi, OFFSET source
mov al, '?'                  ; search for ?
mov ecx, LENGTHOF source
cld
repne scasb       ; repeat while not equal
jnz quit
dec edi           ; edi points to ?

end main

Answer 1

您可以在＆＃34;？＆＃34;之后更换所有内容。由零，所以＃34;？＆＃34;之后的所有字符已被删除＆＃34; ：

INCLUDE Irvine32.inc

.data
source BYTE "Is this a string? Enter y for yes, and n for no",0

.code
main PROC

mov edi, OFFSET source
mov al, '?'                  ; search for ?
mov ecx, LENGTHOF source
cld
repne scasb       ; repeat while not equal
jnz quit
dec edi           ; edi points to ?

;REPLACE ALL CHARACTERS BY "AL" (ZERO) STARTING WHERE "EDI" WAS AND
;FINISH WHEN "ECX" == 0.
mov al, 0         ;<=====================================
repne stosb       ;<=====================================

end main

注意我们在搜索＆＃34;？＆＃34;后如何使用EDI和ECX的值。