Date convertion to SharePoint DateTime

Ref:

http://www.mindfiresolutions.com/Format-Input-for-SharePoint-DateTime-field-186.php

/* -- Format for Date Only Field -- */      

private static String ToSPDate(String strDt)

{

    if (strDt == String.Empty)

        return strDt;

    else

        return (Convert.ToDateTime(strDt)).ToString("yyyy-MM-dd");

}

/* -- Format for DateTime Field -- */

private static String ToSPDateTime(String strDt)

{

    if (strDt == String.Empty)

        return strDt;

    else

        return (Convert.ToDateTime(strDt)).ToString("yyyy-MM-ddTHH:mm:ssZ");

}

/* -- Build List WebReference CAML String -- */

String strCamlBuilder = "<Method ID='1' Cmd='Update'>";

strCamlBuilder += "<Field Name='ID'>1</Field>";

strCamlBuilder += "<Field Name='DateOnlyField'>" +ToSPDate(strDtInput) + "</Field>";

strCamlBuilder += "<Field Name='DateTimeField'>" +ToSPDateTime(strDtTmInput) + "</Field>";

strCamlBuilder += "</Method>";