"&_"在VB中意味着什么？

Question

我正在将一些查询语句从旧版VB应用程序复制到C#应用程序.我不熟悉VB,虽然看着它让我想要一个VB(Victoria Bitter).我遇到过像这样构造的查询:

*SELECT dp_duckbill_accounts.platypus_no AS duckbill, t_accounts.name AS Name " & _ 
"FROM t_accounts INNER JOIN dp_duckbill_accounts ON  t_accounts.account_no = dp_duckbill_accounts.account_no " & _
"ORDER BY dp_duckbill_accounts.platypus_no*

"&_"让我停下来.如果它只是"&"我认为它对应于C#中的"+"来连接字符串.但是,世界上的下划线是什么呢？请注意,&符号和下划线由空格分隔.

Answer 1

下划线是线条延续字符.它允许连接包含不同的行.像这样:

x = "Hello " & "World"

x = "Hello " & _
    "World"

'this won't compile (pre vb.net 2010, anyway)
    x = "Hello " & 
    "World"

MSDN上的行继续

如何:在代码中断开和组合语句(Visual Basic)

Answer 2

_ 意味着继续下一行的声明.

所以... & _意味着继续连接以下行的字符串.

text = "One line string"
text = "Two line " & _
       "string"