在解决方案中构建MVC项目时出现此错误.在我的解决方案中根本不存在对这些文件的引用.
C:\Program Files (x86)\MSBuild\14.0\bin\Microsoft.Common.CurrentVersion.targets(4105,5): error MSB3030: Could not copy the file "D:\bootmgr" because it was not found.
1>C:\Program Files (x86)\MSBuild\14.0\bin\Microsoft.Common.CurrentVersion.targets(4105,5): error MSB3030: Could not copy the file "D:\BOOTNXT" because it was not found.
1>C:\Program Files (x86)\MSBuild\14.0\bin\Microsoft.Common.CurrentVersion.targets(4105,5): error MSB3030: Could not copy the file "D:\pagefile.sys" because it was not found.
1>C:\Program Files (x86)\MSBuild\14.0\bin\Microsoft.Common.CurrentVersion.targets(4105,5): error MSB3030: Could not copy the file "D:\swapfile.sys" because it was not found.
我的同事可以毫无错误地建立.
我想计算具有不同where子句的表的值,并想知道是否有更好的方法.
在这段代码中,我算一个值.
SELECT v.name, count(v.value) AS v1
FROM dbo.table as v
WHERE v.organisationID = 2
AND v.datecreated > '2018-01-01'
AND v.datecreated < '2018-05-01'
AND v.value = 1
GROUP BY v.name
我还想计算所有值为value = 2的行,我的方式是这样的,使用子选择.
SELECT v.name, count(v.value) AS v1, (SELECT v2.name, count(v2.value)
FROM dbo.table as v2
WHERE v2.organisationID = 2
AND v2.datecreated > '2018-01-01'
AND v2.datecreated < '2018-05-01'
AND v2.value = 2
GROUP BY v2.name) AS v2
FROM dbo.table as v
WHERE v.organisationID = 2
AND v.datecreated > '2018-01-01'
AND v.datecreated …我收到这样的错误消息：
SqlParameterCollection仅接受非null的SqlParameter类型对象，而不接受String对象
在此代码上：
.Parameters.Add(new SqlParameter("@username", SqlDbType.NVarChar,128).Value = username);
如果我将其更改为：
.Parameters.Add(new SqlParameter("@username", SqlDbType.NVarChar,128).SqlValue = username);
不应该只重视工作吗？
sqlValue不是数据库类型吗？
这是我使用的DAL：
public class DBAccess : IDisposable
{
private IDbCommand cmd = new SqlCommand();
private string strConnectionString = "";
private bool handleErrors = false;
private string strLastError = "";
public DBAccess()
{
strConnectionString = ConfigurationManager.ConnectionStrings["DB"].ConnectionString;
SqlConnection cnn = new SqlConnection();
cnn.ConnectionString = strConnectionString;
cmd.Connection = cnn;
cmd.CommandType = CommandType.StoredProcedure;
}
public CommandType CommandType
{
get
{
return cmd.CommandType;
}
set
{
cmd.CommandType = value;
} …