How to add seconds to the value of DateTimePicker?

I need to add seconds to 开发者_运维技巧the value of DateTimePicker. Can anyone tell me why the value remains unchanged after executing following code? And also I want to change the displayed value of DateTimePicker to its new value. This should be easy. mmm I dont know why.

Thanks.

protected override void updateTime(uint seconds)
{
    this.dtPicAdmitDate.Value.AddSeconds(seconds);
}

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AddSeconds() will return a new DateTime object. Try:

this.dtPicAdmitDate.Value = this.dtPicAdmitDate.Value.AddSeconds(seconds);