How to convert C# datetime to MySql Datetime format. I am getting value from text box like 7/27/2011 this format. But i want to convert in this format 2011-7-27. So here i am stuking. Please help me. My objective is to filter the record between two dates and show in a listview control in asp.net.
Here is my code:
DateTime dt1 = Convert.ToDateTime(txtToDate.Text);
DateTime dt2 = Convert.ToDateTime(txtFromDate.Text);
lvAlert.DataSource = facade.GetAlertsByDate(dt1, dt2);
lvAlert.DataBind();
I haven't used MySQL with .NET, but Oracle has similar date conversion issues with .NET. The only way to stay snae with this has been to use parameters for date values, both for input as welll as for WHERE clause comparisons. A parameter created with a MySQL date parameter type, and just giving it a .NET datetime value, should work without needing you to do conversions.
EDITED TO ADD SAMPLE CODE
This code sample shows the basic technique of using parameters for DateTime values, instead of coding conversions to text values and embedding those text values directly in the SQL command text.
public DataTable GetAlertsByDate(DateTime start, DateTime end)
{
SqlConnection conn = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand(
"SELECT * FROM Alerts WHERE EventTime BETWEEN #start AND #end", conn);
DataTable table = new DataTable();
try
{
SqlParameter param;
param = new SqlParameter("#start", SqlDbType.DateTime);
param.Value = start;
cmd.Parameters.Add(param);
param = new SqlParameter("#end", SqlDbType.DateTime);
param.Value = end;
cmd.Parameters.Add(param);
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(table);
}
finally
{
cmd.Dispose();
conn.Close();
conn.Dispose();
}
return table;
}
This is SQL Server code, but the technique should be the same for most databases. For Oracle, for example, the only changes would be to use Oracle data access objects, and use ":" in place of "#" in parameter names. The technique for MySQL should also be very similar.
For many databases, shortcuts may exist for creating parameters, such as:
cmd.Parameters.AddWithValue("#start", start);
This works when you know the value is not null, and the correct parameter type can be derived from the C# type of the value. "AddWithValue" is specific to SQL Server; "Add" works also but is obsolete in SQL Server.
Hope this helps.
You can assign format to data time, DateTime.ParseExact() or DateTime.ToString(format), :
the format for 2011-7-27 is yyyy-m-dd
Assuming you are doing this in the database I think you should use date_format to get in the required format
Something like date_format(dateval,'%Y-%c-%d') (Not tested)
I use:
string fieldate = dt1.ToString("yyyy-MM-dd");
Related
I have a date and time loaded into a textbox for editing, but I need to store it as a datetime in my access database not a string and cannot remember or find the syntax to parse it in my SQL parameters... here is my code anyway...
string strSql = "UPDATE OCR SET OCR = #OCR, [OCR Title] = #OCRTitle, DeadlineDate = #DeadlineDate;";
using (OleDbConnection newConn = new OleDbConnection(strProvider))
{
using (OleDbCommand dbCmd = new OleDbCommand(strSql, newConn))
{
dbCmd.CommandType = CommandType.Text;
dbCmd.Parameters.AddWithValue("#OCRTitle", textBox6.Text);
dbCmd.Parameters.AddWithValue("#OCR", textBox5.Text);
dbCmd.Parameters.AddWithValue("#DeadlineDate", textBox7.Text);
newConn.Open();
dbCmd.ExecuteNonQuery();
}
}
You're specifying a string as the deadline date value. You should specify a DateTime instead.
You can use DateTime.Parse (or DateTime.ParseExact, or DateTime.TryParseExact) to parse the text representation if you really have to - but it would be better to use a date-based control to start with, rather than having a text representation at all.
(It's not clear what sort of application this is - WinForms, ASP.NET etc - but most GUIs have some sort of date picker these days.)
EDIT: Additionally, you need to change the order in which you add the parameters to the command such that it matches the order in which the parameters are used in the SQL statement. These are effectively positional parameters - the names are ignored. It would probably be clearer to use ? than named parameters in the SQL.
I use GETDATE() in a SQL Server stored procedure to insert a date into the SQL Server database table.
After that I need to implement a C# function which is based on datetime input parameter finds if the date was saved in the tables.
The datetime in C# and SQL are different. How do I convert from C# datetime to SQL datetime which has a form of yyyy-mm-ddT:yy:mm:ss.mmm? I need to specify explicitly yyyy-mm-ddT:yy:mm:ss.mmm.
Will be happy for all propositions/possible ways.
DateTime in .Net framework and SQL Server (if it is DateTime type field) is irrespective of the format. Format is only useful for displaying output.
If your field in SQL Server is of DateTime type then you can query it from C# code using parameterized query something like:
public DataTable GetRecords(DateTime dtParameter)
{
DataTable dt = null;
using (SqlConnection conn = new SqlConnection("connection string"))
{
using (SqlCommand cmd = new SqlCommand("SELECT * from yourTable where DateField = #dateparameter"))
{
conn.Open();
cmd.Parameters.AddWithValue("#dateparameter",dtParameter);
SqlDataReader dr = cmd.ExecuteReader();
//...rest of the code
dt.Load(dr);
}
}
return dt;
}
Datetimes between C# and SQL are 100% compatible. The format shouldn't make any difference if you are passing them as DateTimes. If you are generating a SQL string then I would highly recommend changing to SQL Parameters so you don;t have to worry about any formatting issues.
A datetime has no format at all, it has a value. SQL-DateTimes and C# DateTimes are compatible. So don't convert it (to string) at all but pass it as datetime-parameter to the database.
Then you're safe if the DateTime value is within SqlDateTime.MinValue(January 1, 1753) and SqlDateTime.MaxValue(December 31, 9999).
You should never write DateTime.Now from client code to insert into the database as this will be based on the clients local time; do this
public DateTime GetDatabaseTime()
{
var parameter = new SqlParameter("time", SqlDbType.DateTime2)
{
Direction = ParameterDirection.Output
};
using (var connection = new SqlConnection(ConnectionString))
{
connection.Open();
using (var command = new SqlConnection("SELECT #time = SYSDATETIME()", connection))
{
command.ExecuteNonQuery();
}
}
return (DateTime)parameter.Value;
}
Also you should never use DATETIME in SQL Server you should always use DATETIME2 as DATETIME is less accurate than C#::DateTime and it will lead to rounding errors. I know this from bitter experience.
If you are using Entity Framework, and your database is using datetime and not datetime2, the trick is to use SqlDateTime to match the fact that .Net goes to nanosecond, versus sql's millisecond precision. You can use your DateTime variable in .net.. for a SqlDateTime instance, and then you can uniquely identify a record down to the millisecond.
System.Data.SqlTypes.SqlDateTime entry2 = new System.Data.SqlTypes.SqlDateTime(new DateTime(dto.LookUpDateTime));
DateTime entry = entry2.Value;
var existticket = from db in context.Tickets
where db.LookupDateTime == entry && db.UserId == UserId
select db;
I'm calling a stored procedure from my code using SqlCommand, some of the parameters are of DateTime type, when calling the procedure from Management Studio I use the following format yyyy-MM-dd for example 2011-01-01, and results are returned accordingly.
In my C# code I'm creating the DateTime object like the following:
DateTime dateFrom = new DateTime(2011,01,01);
and when I run the application the dates are being complete ignored and all the data is being returned. After the debugging accordingly I'm noticing that the format of the DateTime object is being: {01/01/2011 00:00:00} so probably this is causing the issue.
The parameters are being added to SqlCommand like this:
cmd.Parameters.AddWithValue("#DateFrom", SqlDbType.DateTime);
Any idea please?
Copying code:
using (SqlConnection conn = new SqlConnection(connectionString))
{
DateTime dateFrom = new DateTime(2011,01,01);
DateTime dateTo = new DateTime(2011, 01, 31);
SqlCommand cmd = new SqlCommand(strStoredProcName, conn);
cmd.CommandType = System.Data.CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("#DateFrom", SqlDbType.DateTime);
cmd.Parameters.AddWithValue("#DateTo", SqlDbType.DateTime);
cmd.Parameters["#DateFrom"].Value = dateFrom;
cmd.Parameters["#DateTo"].Value = dateTo;
}
There should be no format issue from C# to SQL for date time data type.
There may be 2 things causing this issue:
As far I can remember, you not need to add # for the parameter name
cmd.Parameters.AddWithValue("DateFrom", SqlDbType.DateTime);
The overload of AddWithValue is string parameterName and object value. You have passed SqlDbType.DateTime as the value. Pass your DateTime variable instead.
you have two options either choose Add or AddWithValue with following format:
1) cmd.Parameters.Add("#DateFrom", SqlDbType.DateTime).Value = dateFrom;
2) cmd.Parameters.AddWithValue("#DateFrom", dateFrom);
If the datetime parameter in stored procedure is type of DateTime, you need not to essentially pass the value as datetime. You can pass simple string value like below:
cmd.Parameters.Add("#DateFrom", SqlDbType.DateTime).Value = "23-03-2013";
my question looks simple: in my client/server application I want to record a specific date provided by the client.
The problem is that I don't know the regional settings of the client, and I don't know the regional settings of the SQL Server.
How can the client application provide a date in whatever format (last login of a specific user) and store it in a SQL Server table that might be installed with a different regional settings (french, english, italian, german, etc...).
Simple: don't use strings. Use a parameter that is typed as a datetime; can be as simple as:
DateTime when = ...
using(var cmd = conn.CreateCommand()) {
cmd.CommandText = "... #when ...";
cmd.Parameters.AddWithValue("when", when);
cmd.ExecuteNotQuery();
}
or with "dapper":
conn.Execute("... #when ...", new { when });
Dates/times are actually just numbers. It is only when you write/parse it as a string that formatting is an issue.
Just store everything in UTC date in sqlserver. And while retrieving the date convert the utc date to the timezone of the user. I hope users timezone is maintained in your database.
You will need a timezone table and a conversion function that will convert the UTC time to the users local time.
to insert a date in SQL use a string in the form 'YYYYMMDD'
what comes from the client-side you sould know what is it
You should use Parameters, but you also can format date to ISO format by date.ToString("s")
Use datetime format, and store dates as UTC time.
You'll probably also be interested in datetimeoffset.
Validation part
DateTime dt;
string YourDate = "Your Date";
if (DateTime.TryParse(YourDate, out dt))
{
//Your Code
}
Stored Procedure Record Insertion/Retrieval
using (System.Data.SqlClient.SqlConnection con = new SqlConnection("YourConnection string"))
{
con.Open();
SqlCommand cmd = new SqlCommand();
string expression = "Date Parameter value";
DateTime dt;
if (DateTime.TryParse(expression, out dt))
{
//Your Code
}
cmd.CommandType = CommandType.StoredProcedure;
cmd.CommandText = "Your Stored Procedure";
cmd.Parameters.Add("Your Parameter Name", SqlDbType.VarChar).Value = expression;
cmd.Connection = con;
using (IDataReader dr = cmd.ExecuteReader())
{
if (dr.Read())
{
}
}
}
While storing the data in Sql Server Keep the data format consistent and synchronized with the data format while retrieving....
I'm trying to insert a datetime value into a datatable and then use the oledbdataadapter's update(datatable) method to load it into my database.. but i keep getting a "Data type mismatch in criteria expression." error. My access Data types in the table are:
ID Number
Nombre_Proyecto Text
Codigo_Ine_Proy Text
Cliente text
Fecha_Creacion Datetime (short date)
according to access short date is mm/dd/yyy, wich fits with my datetime/toshortdatestring method? i think so at least.
Any help would be appreciated. Here's my code:
Insert OledbCommand fot the data adapter:
sql = "PARAMETERS [#Fecha_Creacion] datetime;INSERT Into [Proyectos] ([ID], [Nombre_Proyecto],[Codigo_Ine_Proy],[Cliente],[Fecha_Creacion]) Values (#ID,#Nombre_Proyecto,#Codigo_Ine_Proy,#Cliente,#Fecha_Creacion)";
Comando = new OleDbCommand(sql, conn);
Comando.Parameters.Add("#Nombre_Proyecto", OleDbType.VarWChar, 500, "Nombre_Proyecto");
Comando.Parameters.Add("#Codigo_Ine_Proy", OleDbType.VarWChar, 500, "Codigo_Ine_Proy");
Comando.Parameters.Add("#Cliente", OleDbType.VarWChar, 500, "Cliente");
Comando.Parameters.Add("#Fecha_Creacion", DbType.DateTime);
Comando.Parameters.Add("#ID", OleDbType.Integer, 10000, "ID");
Part where i create the datarow on my datatable:
DataRow newRow = Tabla_Proyectos_BD_General.NewRow();
Max_IDs["Proyectos"] += 1;
newRow["ID"] = Max_IDs["Proyectos"];
newRow["Nombre_Proyecto"] = textBox2.Text;
newRow["Codigo_Ine_Proy"] = textBox1.Text;
newRow["Cliente"] = textBox3.Text;
string x = System.DateTime.Now.ToShortDateString();
newRow["Fecha_Creacion"] = x;
Tabla_Proyectos_BD_General.Rows.Add(newRow);
You should just use
newRow["Fecha_Creacion"] = System.DateTime.Now;
What you see from in the Access is the "formatted date". When interacting thru OleDB you need to use the DateTime and not the formatted string.
string x = System.DateTime.Now.ToShortDateString();
It's a string, not a datetime! hence mismatch.
newRow["Fecha_Creacion"] = System.DateTime.Now;
And your parameterised query should just do it for you.
if you want to show the date you put in there in shortdatestring format (whate ever that is on the pc that does the formatting, get it as a datetime and then format as required.
PS if you want to pass a date as a string to a database, use the formats yyyy-MM-dd or yyyyMMdd. Any other than the universal and unambiguous date formats is just a bug waiting to happen, and never do unless you have to.
Tip when outputting dates, converting them into strings in some format is the last operation, when inputing them, converting to a datetime from the string is the first thing you should do.
Edited after comment
Simplest solution is
Comando.Parameters.Add("#Fecha_Creacion", DbType.DateTime, System.DateTime.Now);