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C# Webservice返回字节数组_C#_Sql_Sql Server_Web Services_Webmethod - Fatal编程技术网

C# Webservice返回字节数组

C# Webservice返回字节数组,c#,sql,sql-server,web-services,webmethod,C#,Sql,Sql Server,Web Services,Webmethod,我有一个Web服务,它从数据库中获取字节[]的列表。我希望能够返回所有的值。如何返回字节[] [WebMethod] public List<fgrTemplate> StudentVerifications() { List<fgrTemplate> listOfFgrTemp = new List<fgrTemplate>(); cn.Open();

我有一个Web服务,它从数据库中获取字节[]的列表。我希望能够返回所有的值。如何返回字节[]

 [WebMethod]
        public List<fgrTemplate> StudentVerifications()
         {
            List<fgrTemplate> listOfFgrTemp = new List<fgrTemplate>();
            cn.Open();
            SqlCommand com = new SqlCommand("SELECT Template FROM tblFingerprint", cn);
            SqlDataReader sr = com.ExecuteReader();
            while (sr.Read())
            {
                fgrTemplate fingerprint = new fgrTemplate()
                {
                    ID = sr.GetInt32(0),
                    StudentID = sr.GetInt32(1),
                    Description = sr.GetString(2)
                    Template = sr.GetByte??
                };
 listOfFgrTemp.Add(fingerprint);
  }

            cn.Close();
            return listOfFgrTemp;

        }
[WebMethod]
公开名单学生验证()
{
List LISTOFFRGTEMP=新列表();
cn.Open();
SqlCommand com=新的SqlCommand(“从tblFingerprint中选择模板”,cn);
SqlDataReader sr=com.ExecuteReader();
while(sr.Read())
{
fgrTemplate指纹=新的fgrTemplate()
{
ID=sr.GetInt32(0),
StudentID=sr.GetInt32(1),
Description=sr.GetString(2)
模板=sr.GetByte??
};
listOfFgrTemp.Add(指纹);
}
cn.Close();
返回listOfFgrTemp;
}
像这样:

Template = (byte[])sr[3];


SQL server中字节数组的数据类型是什么?模板的数据类型是imageyou't not besides
sr.getBytes()
?以下内容可能会有所帮助,因为它给出了示例代码:谢谢,这很有效,但当我尝试运行应用程序时,m_storedtemplate返回空值。fgrTemplate[]m_storedtTemplate=verify.studentverifyments();
Template = (byte[])sr["Template"];