C＃.Net中的连接字符串

Question

// SQL PART

第1行：string dd = "Data Source=.\SQLEXPRESS;AttachDbFilename="C:\Users\HEX\Documents\Visual Studio 2008\Projects\cventry_address_book_0.1\cventry_address_book_0.1\addressbook.mdf";Integrated Security=True;Connect Timeout=30;User Instance=True";

第2行：SqlConnection sqlconobj = new SqlConnection(dd);

第3行：sqlconobj.Open();

--------- 错误输出 ------------

意外字符'\'

Answer 1

在C＃中，反斜杠字符具有特殊含义。您需要将其加倍或在整个字符串前加上Verbatim字符@并且无需在文件名前后加上双引号。格式设置规则（以分号结尾）在AttachDbFileName的路径或文件名中保留空格

 string dd = @"Data Source=.\SQLEXPRESS;AttachDbFilename=" + 
             @"C:\Users\HEX\Documents\Visual Studio 2008\" + 
             @"Projects\cventry_address_book_0.1\cventry_address_book_0.1" + 
             @"\addressbook.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True";

Answer 2

尝试：

string dd = @"Data Source=.\SQLEXPRESS;AttachDbFilename=""C:\Users\HEX\Documents\Visual Studio008\Projects\cventry_address_book_0.1\cventry_address_book_0.1\addressbook.mdf"";Integrated Security=True;Connect Timeout=30;User Instance=True";

您需要使用@字符对字符串进行转义。或者，您可以将单个\替换为\\。

Answer 3

您应通过在字符串前面加上@字符来对其进行转义。另外，您还应该在using语句中包装SqlConnection实例：

string dd = @"Data Source=.\SQLEXPRESS;AttachDbFilename=""C:\Users\HEX\Documents\Visual Studio 2008\Projects\cventry_address_book_0.1\cventry_address_book_0.1\addressbook.mdf"";Integrated Security=True;Connect Timeout=30;User Instance=True";
using (SqlConnection sqlconobj = new SqlConnection(dd))
{
    sqlconobj.Open();
}

Answer 4

您需要转义\字符。使用这个：

string dd = @"Data Source=.\SQLEXPRESS;AttachDbFilename="C:\Users\HEX\Documents\Visual Studio 2008\Projects\cventry_address_book_0.1\cventry_address_book_0.1\addressbook.mdf";Integrated Security=True;Connect Timeout=30;User Instance=True";

更多：String literals

Answer 5

string dd = "Data Source=.\\SQLEXPRESS;AttachDbFilename=\"C:\\Users\\HEX\\Documents\\Visual Studio 2008\\Projects\\cventry_address_book_0.1\\cventry_address_book_0.1\\addressbook.mdf\";Integrated Security=True;Connect Timeout=30;User Instance=True";

Answer 6

这应该是您的查询连接字符串

string dd = @"Data Source=.\SQLEXPRESS;AttachDbFilename=" + 
                            @"C:\Users\HEX\Documents\Visual Studio 2008\Projects\cventry_address_book_0.1\cventry_address_book_0.1\addressbook.mdf" 
                            + ";Integrated Security=True;Connect Timeout=30;User Instance=True";