将字符串转换为12小时格式的日期时间格式

Question

I am having a field type DateTime in SQL server database. I am developing a webservice to fetch date and time.

The date is stored in this format 4/14/2013 10:10:01 PM in database.

Now, I have a webmethod as below:

public string GetdataJson(string lastdate)
        {

            DateTime myDateTime = DateTime.Parse(lastdate);


            string getvalue = "select * from tblfameface where last_updated >='" + myDateTime  + "'";

            con1 = new SqlConnection(conString1);
            con1.Open();
            SqlCommand cmd = new SqlCommand(getvalue, con1);
            SqlDataAdapter da = new SqlDataAdapter(cmd);
            DataTable dt1 = new DataTable();
            da.Fill(dt1);

            string jsonString = JsonConvert.SerializeObject(dt1);
            String finalString = "{\"Records\":";
            finalString += jsonString;
            finalString += "}";
            return finalString;

        }

But this code is giving me an error of String was not recognized as a valid DateTime. how can I convert string into datetime format like 4/14/2013 10:10:01 PM?? help!

Answer 1

You want 12-hour clock use small hh , You want the 24-hour clock use capital HH

DateTime formatted =Covert.ToDateTime( lastdate.ToString("dd/MM/yyyy hh:mm:ss.fff",
                                      CultureInfo.InvariantCulture));

If you want to use the 12-hour clock, use tt in the format string to produce the AM/PM designator.

Answer 2

In your format string use tt for PM/AM part. Here is the code:

 DateTime dateTime = 
    DateTime.ParseExact("4/14/2013 10:10:01 PM", 
                        "M/dd/yyyy hh:mm:ss tt",
                        System.Globalization.CultureInfo.InvariantCulture);

This should also works:

DateTime result = DateTime.Parse("04/14/2013 10:10:01 PM");

Are you sure you are getting the correct string?

Answer 3

使用此代码

DateTime.ParseExact(yourString, "MM/dd/yyyy hh:mm:ss tt");

Answer 4

Try this:

string getvalue = "select * from tblfameface where
     last_updated >= Convert(DateTime, '" + myDateTime  + "')";

or this depending on you SQL data type on column last_updated

string getvalue = "select * from tblfameface where
     last_updated >= Convert(DateTime2(7), '" + myDateTime  + "')";

Answer 5

Replace query line by

string getvalue = "select * from tblfameface where CAST(last_updated AS 
DATETIME)>='" + myDateTime.ToString("dd/MM/yyyy hh:mm:ss tt")  + "'";