Convert dotnet DateTime to Sqlserver SqlDateTime
The SqlDateTime has a narrower span than the Dotnet ditto; dotnet starts from year 0 but sqlserver from 1753. This means that uninitialised DateTime fields in dotnet will give runtime execution errors when trying to persist them in a sqlserver database.
I write together a small and simple method for making sure the DateTime interval is inside the valid SqlDateTime interval.
public static class DateTimeExtensions
{
/// <summary>This method returns the datetime fitting into min/max of Sqlserver
/// as per http://codebetter.com/petervanooijen/2008/08/21/valid-date-time-values-in-sql-server-sqldatetime-vs-datetime/
/// </summary>
/// <param name="dt"></param>
/// <returns></returns>
public static DateTime ToValidSqlserverDatetime(this DateTime dt)
{
// Must cast System.Data.SqlTypes.SqlDateTime.MinValue: http://codebetter.com/petervanooijen/2008/08/21/valid-date-time-values-in-sql-server-sqldatetime-vs-datetime/
if (dt < (DateTime)System.Data.SqlTypes.SqlDateTime.MinValue)
{
return (DateTime)System.Data.SqlTypes.SqlDateTime.MinValue;
}
else if (dt > (DateTime)System.Data.SqlTypes.SqlDateTime.MaxValue)
{
return (DateTime)System.Data.SqlTypes.SqlDateTime.MaxValue;
}
else
{
return dt;
}
}
}
The code is easier to read at pastebin.
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Here is a short example:
var nameList = myFacade.GetData(). where( x => x.ID = 42 ). select( x => x.Name ). ToList();
which in VBNet becomes:
Dim nameList = myFacade.GetData(). Where( Function(x) x.ID = 42 ). Select( Function(x) x.Name ). ToList()
Note that the periods have to be at the end of the line, otherwise the multi line capability of Vbnet doesn’t work. This can be remedied by the old trailing underscore of VB.
If you need to set the type of x it is also doable:
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"mystring".ToUpper()
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char.ToUpper('x')
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Below is linked a good article. I don’t consider it as wordy since it really explains the subject in depth in a simple way.
There are 6 examples where 4 can be used. At the bottom of the article is a short explanation if you don’t want to grok it.