无法将 MySQL 日期/时间值转换为 System.DateTime

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Let MySql convert your unix timestamp to string. Use the mysql function FROM_UNIXTIME( 113283901 )

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Pull the datetime value down as a string and do a DateTime.ParseExact(value, "ddd MMM dd hh:mm:ss yyyy", culture, styles); You would just need to set the date format up for the date you are returning from the database. Most likely it's yyyy-MM-dd HH:mm:ss. At least is is for me.

Check here more info on the DateTime.ParseExact

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最佳答案

If I google for "Unable to convert MySQL date/time value to System.DateTime" I see numerous references to a problem accessing MySQL from Visual Studio. Is that your context?

One solution suggested is:

This is not a bug but expected behavior. Please check manual under connect options and set "Allow Zero Datetime" to true, as on attached pictures, and the error will go away.

Reference: http://bugs.mysql.com/bug.php?id=26054

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You must add Convert Zero Datetime=True to your connection string, for example:

server=localhost;User Id=root;password=mautauaja;Persist Security Info=True;database=test;Convert Zero Datetime=True

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i added both Convert Zero Datetime=True & Allow Zero Datetime=True and it works fine

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I also faced the same problem, and get the columns name and its types. Then cast(col_Name as Char) from table name. From this way i get the problem as '0000-00-00 00:00:00' then I Update as valid date and time the error gets away for my case.

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You can make the application fully compatible with the date and time that is used by MySql. When the application runs at runtime provide this code. First Go to the Application Events. In the list of tools

Go to the project
Project Properties
Select the Application tab
View Application Events

This will open a new file. This file contains code used at the start of the application.

Write this code in that new file:

 Partial Friend Class MyApplication


Private Sub MyApplication_Startup(ByVal sender As Object, ByVal e As Microsoft.VisualBasic.ApplicationServices.StartupEventArgs) Handles Me.Startup
My.Application.ChangeCulture("en")
My.Application.ChangeUICulture("en")
My.Application.Culture.DateTimeFormat.ShortDatePattern = "yyyy-MM-dd"
My.Application.Culture.DateTimeFormat.LongDatePattern = "yyyy-MM-dd"
My.Application.Culture.DateTimeFormat.LongTimePattern = "HH:mm:ss"
My.Application.Culture.DateTimeFormat.ShortTimePattern = "HH:mm:ss"
End Sub




End Class

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Rather than changing the connection string, you can use the IsValidDateTime property of the MySqlDateTime object to help you determine if you can cast the object as a DateTime.

I had a scenario where I was trying to load data from an "UpdateTime" column that was only explicitly set when there was an update to the row (as opposed to the InsertedTime which was always set). For this case, I used the MySqlDataReader.GetMySqlDateTime method like so:

using (MySqlDataReader reader = await MySqlHelper.ExecuteReaderAsync(...))
{
if (await reader.ReadAsync())
{
DateTime? updateTime = reader.GetMySqlDateTime("UpdateTime").IsValidDateTime ? (DateTime?)reader["UpdateTime"] : null;
}
}

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if "allow zero datetime=true" is not working then use the following sollutions:-

Add this to your connection string: "allow zero datetime=no" - that made the type cast work perfectly.

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In a Stimulsoft report add this parameter to the connection string (right click on datasource->edit)

Convert Zero Datetime=True;

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When you're using EF edmx with MySql, please review the Precision attribute in the entitytype.

<EntityType Name="table">
<Key>
<PropertyRef Name="Id" />
</Key>
<Property Name="Id" Type="int" StoreGeneratedPattern="Identity" Nullable="false" />
<Property Name="date_field" Type="datetime" Precision="0" Nullable="false" />
</EntityType>

If you made changes in the datetime field, it could be possible you're missing this attribute in the property.