我该如何逃脱！所以终端看到 echo "Hello World!" 的结束 dquote
How do I escape an ! so terminal sees a closing dquote for echo "Hello World!"
问题：
通过在终端中输入 echo "Hello World!"，我得到的答复是：dquote>
问题（2 部分）：
如果我使用单引号，终端 returns 我期望看到的结果：Hello World!
- 如何逃脱
!？
- 这里为什么双引号和单引号不同？
我试过了：
用反斜杠，echo "Hello World/!"好像不行，我还是被退回了dquote>。
我还尝试寻找有关转义字符和 Whosebug 答案的其他答案。他们通常最终会超越我的头脑。
关于问题 1：(如何转义 !?)
您可以使用"'!'"
示例：
echo "Hello World"'!'""'!'" I'm there."
结果：
Hello World!! I'm there.
关于问题2：（这里为什么双引号和单引号不同？）
因为!是默认的"history expansion"字符，里面的双引号"history expansion"被执行。
Bash 手册：
Enclosing characters in single quotes (') preserves the literal value of each character within the quotes. A single quote may not occur between single quotes, even when preceded by a backslash.
Enclosing characters in double quotes (") preserves the literal value of all characters within the quotes, with the exception of $, `, \, and, when history expansion is enabled, !. The characters $ and ` retain their special meaning within double quotes (see Shell Expansions). The backslash retains its special meaning only when followed by one of the following characters: $, `, ", \, or newline. Within double quotes, backslashes that are followed by one of these characters are removed. Backslashes preceding characters without a special meaning are left unmodified. A double quote may be quoted within double quotes by preceding it with a backslash. If enabled, history expansion will be performed unless an ! appearing in double quotes is escaped using a backslash. The backslash preceding the ! is not removed.
The special parameters * and @ have special meaning when in double quotes (see Shell Parameter Expansion).
问题：
通过在终端中输入 echo "Hello World!"，我得到的答复是：dquote>
问题（2 部分）：
如果我使用单引号，终端 returns 我期望看到的结果：Hello World!
- 如何逃脱
!？ - 这里为什么双引号和单引号不同？
我试过了：
用反斜杠，echo "Hello World/!"好像不行，我还是被退回了dquote>。
我还尝试寻找有关转义字符和 Whosebug 答案的其他答案。他们通常最终会超越我的头脑。
关于问题 1：(如何转义 !?)
您可以使用"'!'"
示例：
echo "Hello World"'!'""'!'" I'm there."
结果：
Hello World!! I'm there.
关于问题2：（这里为什么双引号和单引号不同？）
因为!是默认的"history expansion"字符，里面的双引号"history expansion"被执行。
Bash 手册：
Enclosing characters in single quotes (
') preserves the literal value of each character within the quotes. A single quote may not occur between single quotes, even when preceded by a backslash.Enclosing characters in double quotes (
") preserves the literal value of all characters within the quotes, with the exception of$,`,\, and, when history expansion is enabled,!. The characters$and`retain their special meaning within double quotes (see Shell Expansions). The backslash retains its special meaning only when followed by one of the following characters:$,`,",\, or newline. Within double quotes, backslashes that are followed by one of these characters are removed. Backslashes preceding characters without a special meaning are left unmodified. A double quote may be quoted within double quotes by preceding it with a backslash. If enabled, history expansion will be performed unless an!appearing in double quotes is escaped using a backslash. The backslash preceding the!is not removed.The special parameters
*and@have special meaning when in double quotes (see Shell Parameter Expansion).