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C Aldair
Asked: 2022-03-25 20:31:52 +0800 CST 2022-03-25 20:31:52 +0800 CST

Error converting string to Datetime in ASP.NET Core

  • 772

I am trying to convert a string to date format in .net Core but it gives me an error when converting it, I am implementing the Convert.ToDateTime(string) in both fields, one in my input variable and another in my ity attribute since it is also a string . What I want is to be able to convert it to a datetime so I can do a date filter from - to and be able to list the dates from that range

this is my code

public List<Stock_Cliente> visualizarMov(StockClienteFil stk)
        {
            DateTime fechaDesde = Convert.ToDateTime(stk.fec_mov_des);
            DateTime fechaHasta = Convert.ToDateTime(stk.fec_mov_has);

            var visualizarMov = _quimpacContex.Stock_Cliente.Where(x => x.stk_cli_des_alm.Contains(stk.des_alm) && x.stk_cli_des_mat.Contains(stk.des_mat)
             && x.stk_cli_num_lot.Contains(stk.num_lot) && x.stk_cli_ser_pre.Contains(stk.ser_pre) && x.stk_cli_buq.Contains(stk.cli_buq)
             && Convert.ToDateTime(x.stk_cli_fec_mov) >= fechaDesde && Convert.ToDateTime(x.stk_cli_fec_mov) >= fechaHasta).ToList();   
            return visualizarMov;
        }

this is my Stock_Customer class

public class Stock_Cliente
    {
        [Key]
        public int stk_cli_cod { get; set; }
        public string stk_cli_cod_cen { get; set; }
        public string stk_cli_des_cen { get; set; }
        public string stk_cli_cod_cli { get; set; }
        public string stk_cli_des_cli { get; set; }
        public string stk_cli_cod_alm { get; set; }
        public string stk_cli_des_alm { get; set; }
        public string stk_cli_num_mat { get; set; }
        public string stk_cli_des_mat { get; set; }
        public string stk_cli_uni_med { get; set; }
        public string stk_cli_num_lot { get; set; }
        public string stk_cli_fec_mov { get; set; }
        public string stk_cli_ser_pre { get; set; }
        public decimal stk_cli_can { get; set; }
        public string stk_cli_buq { get; set; }
        public string stk_cli_fec_lle { get; set; }
        public string stk_cli_hor_lle { get; set; }
        public string stk_cli_fec_sal { get; set; }
        public string stk_cli_hor_sal { get; set; }
        public string stk_cli_est { get; set; }
        public DateTime? stk_cli_fec_cre { get; set; }
        public string? stk_cli_usu_cre_sap { get; set; }
        public DateTime? stk_cli_fec_mod { get; set; }
        public string? stk_cli_usu_mod_sap { get; set; }
    }

this is the json i send you

{
    "des_alm":"Tanque TKG13",
    "des_mat":"ACEITE",
    "num_lot":"CN-S",
    "ser_pre":"Despacho",
    "cli_buq":"PAB4168",
    "fec_mov_des":"20/12/2019",
    "fec_mov_has":"25/03/2019"
}

this is the error that generates me

System.InvalidOperationException: 'The LINQ expression 'DbSet<Stock_Cliente>()
.Where(s => s.stk_cli_des_alm.Contains(__stk_des_alm_0) && 
s.stk_cli_des_mat.Contains(__stk_des_mat_1) && 
s.stk_cli_num_lot.Contains(__stk_num_lot_2) && 
s.stk_cli_ser_pre.Contains(__stk_ser_pre_3) && 
s.stk_cli_buq.Contains(__stk_cli_buq_4) && 
Convert.ToDateTime(s.stk_cli_fec_mov) >= __fechaDesde_5 && 
Convert.ToDateTime(s.stk_cli_fec_mov) >= __fechaHasta_6)'
could not be translated. Additional information: 
Translation of method 'System.Convert.ToDateTime' failed. If this method can be mapped to your custom function, see https://go.microsoft.com/fwlink/?linkid=2132413 for more information.
Translation of method 'System.Convert.ToDateTime' failed. If this method can be mapped to your custom function, see https://go.microsoft.com/fwlink/?linkid=2132413 for more information. Either rewrite the query in a form that can be translated, or switch to client evaluation explicitly by inserting a call to 'AsEnumerable', 'AsAsyncEnumerable', 'ToList', or 'ToListAsync'. See https://go.microsoft.com/fwlink/?linkid=2101038 for more information.'

this is my table in my bd

enter image description here

sql-server

1 Answers

  1. Best Answer

    The method you are using cannot be translated by the EF (Convert.ToDateTime), so I recommend you do the following.

    var visualizarMov = _quimpacContex.Stock_Cliente
            .Where(x => x.stk_cli_des_alm.Contains(stk.des_alm) 
             && x.stk_cli_des_mat.Contains(stk.des_mat)
             && x.stk_cli_num_lot.Contains(stk.num_lot) 
             && x.stk_cli_ser_pre.Contains(stk.ser_pre) 
             && x.stk_cli_buq.Contains(stk.cli_buq))
             .ToList()
             .Where(x=> Convert.ToDateTime(x.stk_cli_fec_mov) >= fechaDesde 
             && Convert.ToDateTime(x.stk_cli_fec_mov) >= fechaHasta).ToList();   
            return visualizarMov;

    In this way, you would do the filter by date range in "memory", in the same way I think it is not necessary to do the Convert.ToDateTime, so you can do the query directly, without using the Convert.

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