看看那一行：

 TextBox6.Text = DateTime.TryParseExact（dateString，format，CultureInfo.InvariantCulture，DateTimeStyles.None， out  dateTime）; 

TryParse / TryParseExact返回一个布尔值：布尔返回值表示解析是成功还是失败。

您应该像以下一样使用它：

  if （！DateTime.TryParseExact（TextBox6.Text，format，CultureInfo.InvariantCulture，DateTimeStyles.None， out  dateTime））
 {
 //  显示一条消息给用户OR  
 //  使用默认值或 
 //  做你认为有用的事情l当TextBox6中的数据不是日期 
}; 

此外，在代码中使用更远的dateTime变量而不是TextBox6。文本！块引用>

Hello ,

I want to particular date data i write some code and also iam using sql server 2008
the column type rdate=datetime some i am given the date in one textbox the textbox
date data can be display the gridview but here is the some error so please help me
i am given the source code

string dateString = TextBox6.Text; // <-- Valid
            string format = "ddd dd MMM h:mm tt yyyy";
            DateTime dateTime;
            TextBox6.Text = DateTime.TryParseExact(dateString, format, CultureInfo.InvariantCulture, DateTimeStyles.None, out dateTime);
            SqlConnection con = new SqlConnection("Data Source=NSYS1\\SQLEXPRESS;Initial Catalog=agfl;connect timeout=30;Integrated Security=True");
            con.Open();
            string strQuery = "select * from stf where  rdate =@some";
            SqlCommand cmd = new SqlCommand(strQuery, con);
            cmd.CommandType = CommandType.Text;
            TextBox6.Text = TextBox6.Text.Trim();
            cmd.Parameters.AddWithValue("@some", TextBox6.Text);
            SqlDataAdapter sda = new SqlDataAdapter(cmd);
            DataTable dt = new DataTable();
            sda.Fill(dt);
            gvuser.DataSource = dt;
            gvuser.DataBind();
            con.Close();

Look at that line:

TextBox6.Text = DateTime.TryParseExact(dateString, format, CultureInfo.InvariantCulture, DateTimeStyles.None, out dateTime);

TryParse / TryParseExact return a Boolean: the boolean return value indicates whether the parsing succeeded or failed.
You ought to use it like:

if (!DateTime.TryParseExact(TextBox6.Text, format, CultureInfo.InvariantCulture, DateTimeStyles.None, out dateTime))
{
    //show a message to the user OR 
    //use a default value OR 
    //do what ever you think is useful when the data in TextBox6 are not a date
};

Also, use the dateTime variable farther down in your code instead of TextBox6.Text!