指定參數的默認值

Question

在vb.net上執行此存儲過程並使購買文本框保持空白以使其在更新時爲空時。但它返回錯誤，說明String未被識別爲有效的DateTime。任何建議，使代碼工作將不勝感激。

CREATE PROCEDURE UpdateEquipmentProfile 

    (
    @OE_ID   varchar(11) = NULL, 
    @OE_Category  char(3)  = NULL, 
    @OE_SubCategory  char(3)  = NULL, 
    @OE_Name   varchar(35) = NULL, 
    @OE_User   varchar(35) = NULL, 
    @OE_Brand   varchar(15) = NULL, 
    @OE_Model   varchar(35) = NULL, 
    @OE_Specs   varchar(1000) = NULL, 
    @OE_SerialNo  varchar(35) = NULL, 
    @OE_PropertyNo  varchar(35) = NULL, 
    @OE_MacAddress  varchar(100) = NULL, 
    @OE_Static_IP  varchar(15) = NULL, 
    @OE_Vendor   varchar(35) = NULL, 
    @OE_PurchaseDate  smalldatetime = NULL, 
    @OE_WarrantyInclusiveYear int  = NULL, 
    @OE_WarrantyStatus  char(2)  = NULL, 
    @OE_Status   varchar(15) = NULL, 
    @OE_Dept_Code  char(3)  = NULL, 
    @OE_Location_Code  char(8)  = NULL, 
    @OE_Remarks   varchar(1000) = NULL 
    ) 

    AS 

    IF EXISTS(SELECT * FROM tblOfficeEquipmentProfile WHERE OE_ID=@OE_ID) 

    UPDATE tblOfficeEquipmentProfile SET 
    OE_Category   =@OE_Category, 
    OE_SubCategory  =@OE_SubCategory, 
    OE_Name   =@OE_Name, 
    OE_User   =@OE_User, 
    OE_Brand   =@OE_Brand, 
    OE_Model   =@OE_Model, 
    OE_Specs   =@OE_Specs, 
    OE_SerialNo   =@OE_SerialNo, 
    OE_PropertyNo  =@OE_PropertyNo, 
    OE_MacAddress  =@OE_MacAddress, 
    OE_Static_IP  =@OE_Static_IP, 
    OE_Vendor   =@OE_Vendor, 
    OE_PurchaseDate  =@OE_PurchaseDate, 
    OE_WarrantyInclusiveYear =@OE_WarrantyInclusiveYear, 
    OE_WarrantyStatus  =@OE_WarrantyStatus, 
    OE_Status   =@OE_Status, 
    OE_Dept_Code  =@OE_Dept_Code, 
    OE_Location_Code  =@OE_Location_Code, 
    OE_Remarks   =@OE_Remarks 

    WHERE OE_ID=@OE_ID 
    GO 

VB.NET代碼

Dim cmd As SqlCommand = sqlconn.CreateCommand 
    sqlconn.Open() 
    cmd.CommandType = CommandType.StoredProcedure 
    cmd.CommandText = "UpdateEquipmentProfile" 

    cmd.Parameters.Add("@OE_ID", SqlDbType.VarChar, 11, "oeq-su-999") 
    cmd.Parameters.Add("@OE_Category", SqlDbType.Char, 3, "COM") 
    cmd.Parameters.Add("@OE_SubCategory", SqlDbType.Char, 3, "SU") 
    cmd.Parameters.Add("@OE_Name", SqlDbType.VarChar, 35, "adminpmis01") 
    cmd.Parameters.Add("@OE_User", SqlDbType.VarChar, 35, "Ivan") 
    cmd.Parameters.Add("@OE_Brand", SqlDbType.VarChar, 15, "DELL") 
    cmd.Parameters.Add("@OE_Model", SqlDbType.VarChar, 35, "optiplex") 
    cmd.Parameters.Add("@OE_Specs", SqlDbType.VarChar, 1000, "dualcore") 
    cmd.Parameters.Add("@OE_SerialNo", SqlDbType.VarChar, 35, "sgh5960") 
    cmd.Parameters.Add("@OE_PropertyNo", SqlDbType.VarChar, 35, "j7h7h6g6f2") 
    cmd.Parameters.Add("@OE_MacAddress", SqlDbType.VarChar, 100, "j7h7:h6g6f2") 
    cmd.Parameters.Add("@OE_Static_IP", SqlDbType.VarChar, 15, "192.168.1.5") 
    cmd.Parameters.Add("@OE_Vendor", SqlDbType.VarChar, 35, "ADWAYS") 
    cmd.Parameters.Add("@OE_PurchaseDate", SqlDbType.SmallDateTime) 
    cmd.Parameters.Add("@OE_WarrantyInclusiveYear", SqlDbType.Int) 
    cmd.Parameters.Add("@OE_WarrantyStatus", SqlDbType.Char, 2, "IN") 
    cmd.Parameters.Add("@OE_Status", SqlDbType.VarChar, 15, "Good") 
    cmd.Parameters.Add("@OE_Dept_Code", SqlDbType.Char, 3, "ADM") 
    cmd.Parameters.Add("@OE_Location_Code", SqlDbType.Char, 8, "ADM_OFC") 
    cmd.Parameters.Add("@OE_Remarks", SqlDbType.VarChar, 1000, "ACTIVE") 
    cmd.Parameters("@OE_ID").Value = txtOEID.Text 
    cmd.Parameters("@OE_Category").Value = cmbCategory.Text 
    cmd.Parameters("@OE_SubCategory").Value = cmbSubCategory.Text 
    cmd.Parameters("@OE_Name").Value = txtName.Text 
    cmd.Parameters("@OE_User").Value = txtUser.Text 
    cmd.Parameters("@OE_Brand").Value = cmbBrand.Text 
    cmd.Parameters("@OE_Model").Value = cmbModel.Text 
    cmd.Parameters("@OE_Specs").Value = txtSpecs.Text 
    cmd.Parameters("@OE_SerialNo").Value = txtSerialNo.Text 
    cmd.Parameters("@OE_PropertyNo").Value = txtPropertyNo.Text 
    cmd.Parameters("@OE_MacAddress").Value = txtMacAddress.Text 
    cmd.Parameters("@OE_Static_IP").Value = txtStaticIp.Text 
    cmd.Parameters("@OE_Vendor").Value = txtVendor.Text 
    cmd.Parameters("@OE_PurchaseDate").Value = txtPurchaseDate.Text 
    cmd.Parameters("@OE_WarrantyInclusiveYear").Value = txtWarrantyInclusiveYear.Text 
    cmd.Parameters("@OE_WarrantyStatus").Value = txtWarrantyStatus.Text 
    cmd.Parameters("@OE_Status").Value = txtStatus.Text 
    cmd.Parameters("@OE_Dept_Code").Value = cmbDeptCode.Text 
    cmd.Parameters("@OE_Location_Code").Value = cmbLocationCode.Text 
    cmd.Parameters("@OE_Remarks").Value = txtRemarks.Text 
    cmd.ExecuteNonQuery() 
    MsgBox("Successfully Updated Equipment Profile") 
    sqlconn.Close() 

Answer 1

Dim d as DateTime 
DateTime.TryParse(txtPurchaseDate.Text, d) 

然後通過d你的存儲過程調用。

cmd.Parameters("@OE_PurchaseDate").Value = d 

Answer 2

因爲參數有NULL的默認值：

@OE_PurchaseDate  smalldatetime = NULL, 

你是不是被迫的值傳遞，如果沒有價值

例如通過：

if txtPurchaseDate.Text <> "" then 
    cmd.Parameters("@OE_PurchaseDate").Value = txtPurchaseDate.Text