VB代码块中选择性注释单行报错，如何实现该操作？

你遇到的错误根源在于VB的多行表达式规则：字符串拼接时，行尾的&用于标记当前表达式未结束，需要延续到下一行。注释中间行后，会破坏这个延续逻辑：

• 被注释行的上一行末尾&没有后续拼接内容，编译器触发BC30201: Expression Expected错误
• 被注释行的下一行开头直接是字符串，缺少前置拼接符号，编译器无法识别为表达式延续，触发BC30035: Syntax error错误

以下是两种可行的解决方法：

方法1：调整拼接符号位置 #

将& vbCrLf &移到每行开头（第一行除外），确保注释任意中间行时，前后行的拼接逻辑依然完整：

Dim someVariable = "this is the first line of a story..." _
& vbCrLf & "this is the second line of a story..." _
& vbCrLf & '"this is the third line, option 1, of a story..." _
& vbCrLf & "this is the third line, option 2, of a story..." _
& vbCrLf & "this is the fourth line of a story..."

也可以省略显式换行符_（VB支持运算符后自动换行），写法更简洁：

Dim someVariable = "this is the first line of a story..." &
vbCrLf & "this is the second line of a story..." &
vbCrLf & '"this is the third line, option 1, of a story..." &
vbCrLf & "this is the third line, option 2, of a story..." &
vbCrLf & "this is the fourth line of a story..."

方法2：使用XML字面量（更推荐） #

VB支持XML字面量，可直接编写多行字符串，用<%-- ... --%>注释任意行，完全不会破坏语法结构，可读性更高：

Dim someVariable = <text>
this is the first line of a story...
this is the second line of a story...
<%-- this is the third line, option 1, of a story... --%>
this is the third line, option 2, of a story...
this is the fourth line of a story...
</text>.Value

XML字面量会自动保留换行格式，无需手动拼接vbCrLf，后续切换注释行只需添加/移除<%-- --%>即可。

内容的提问来源于stack exchange，提问作者Turnip