error: Specified cast is not valid.

Abhilash J A

Hello everyone,

After implement this code,

If LoginTime or LogOutTime is existing null then the error is happening "Specified cast is not valid."

How can I solve this error?

3 Replies

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Prakash Kumar9y ago
Hi Abilash,

In database i think your storing like a string value, see the below
var dt = new DataTable();
dt.Columns.Add("AsString", typeof(string));
dt.Columns.Add("AsDateTime", typeof(DateTime));
var now = DateTime.Now;
var row = dt.Rows.Add(now.ToString(), now);

row.Field<string>("AsString");     // this is fine
row.Field<string>("AsDateTime");   // InvalidCastException: Unable to cast object of type 'System.DateTime' to type 'System.String'.
row.Field("AsString");   // InvalidCastException: Specified cast is not valid.
row.Field("AsDateTime"); // this is fine
DateTime.Parse(row.Field<string>("AsString")); // this is fine
hope it will help you.
Abhilash J A9y ago
Hello Manas,

Both are datetime format in MySql server database.

LogInTime = '2016-12-05 18:39:02.668073' or null

LogOutTime = '2016-12-05 22:39:02.668073' or null
Manas Mohapatra9y ago
What is the value you are getting in LogInTime or LogOutTime variable.