Thuộc tính loại ADO
❮ Tham chiếu đối tượng trường hoàn chỉnh
Thuộc tính Type đặt hoặc trả về giá trị DataTypeEnum cho biết kiểu của một đối tượng Parameter, Field hoặc thuộc tính.
| Object | Description of the Type Property |
|---|---|
| Parameter | The Type property has read/write permissions on a Parameter object |
| Field | The Type property is read/write, with one exception; for new Field objects that are added to the Fields collection of a Record, this property is read-only before the Value property has been set and before the provider has called the Update method of the Fields collection |
| Property | The Type property is read-only for a Property object |
Cú pháp
objectname.Type
Ví dụ - Đối với một đối tượng Trường
<%
set conn=Server.CreateObject("ADODB.Connection")
conn.Provider="Microsoft.Jet.OLEDB.4.0"
conn.Open "c:/webdata/northwind.mdb"
set rs = Server.CreateObject("ADODB.Recordset")
rs.open "Select * from orders", conn
response.write(rs.Fields(0).Type)
rs.Close
conn.close
%>
Ví dụ - Đối với một đối tượng Tham số
<%
set comm=Server.CreateObject("ADODB.Command")
set para=Server.CreateObject("ADODB.Parameter")
para.Type=adVarChar
para.Size=25
para.Direction=adParamInput
para.Value=varfname
comm.Parameters.Append para
%>
Ví dụ - Đối với một đối tượng Thuộc tính
<%
set conn=Server.CreateObject("ADODB.Connection")
conn.Provider="Microsoft.Jet.OLEDB.4.0"
conn.Open "c:/webdata/northwind.mdb"
set rs = Server.CreateObject("ADODB.Recordset")
rs.open "Select * from orders", conn
set prop=Server.CreateObject("ADODB.Property")
'Display the property attributes of the Orders Table
for each prop in rs.Properties
response.write("Attr:" & prop.Attributes & "<br>")
response.write("Name:" & prop.Name & "<br>")
response.write("Value:" & prop.Value & "<br>")
next
rs.close
conn.close
set rs=nothing
set conn=nothing
%>
Giá trị DataTypeEnum
Chỉ định kiểu dữ liệu của đối tượng Trường, Tham số hoặc Thuộc tính
| Constant | Value | Description |
|---|---|---|
| adEmpty | 0 | No value |
| adSmallInt | 2 | A 2-byte signed integer. |
| adInteger | 3 | A 4-byte signed integer. |
| adSingle | 4 | A single-precision floating-point value. |
| adDouble | 5 | A double-precision floating-point value. |
| adCurrency | 6 | A currency value |
| adDate | 7 | The number of days since December 30, 1899 + the fraction of a day. |
| adBSTR | 8 | A null-terminated character string. |
| adIDispatch | 9 | A pointer to an IDispatch interface on a COM object. Note: Currently not supported by ADO. |
| adError | 10 | A 32-bit error code |
| adBoolean | 11 | A boolean value. |
| adVariant | 12 | An Automation Variant. Note: Currently not supported by ADO. |
| adIUnknown | 13 | A pointer to an IUnknown interface on a COM object. Note: Currently not supported by ADO. |
| adDecimal | 14 | An exact numeric value with a fixed precision and scale. |
| adTinyInt | 16 | A 1-byte signed integer. |
| adUnsignedTinyInt | 17 | A 1-byte unsigned integer. |
| adUnsignedSmallInt | 18 | A 2-byte unsigned integer. |
| adUnsignedInt | 19 | A 4-byte unsigned integer. |
| adBigInt | 20 | An 8-byte signed integer. |
| adUnsignedBigInt | 21 | An 8-byte unsigned integer. |
| adFileTime | 64 | The number of 100-nanosecond intervals since January 1,1601 |
| adGUID | 72 | A globally unique identifier (GUID) |
| adBinary | 128 | A binary value. |
| adChar | 129 | A string value. |
| adWChar | 130 | A null-terminated Unicode character string. |
| adNumeric | 131 | An exact numeric value with a fixed precision and scale. |
| adUserDefined | 132 | A user-defined variable. |
| adDBDate | 133 | A date value (yyyymmdd). |
| adDBTime | 134 | A time value (hhmmss). |
| adDBTimeStamp | 135 | A date/time stamp (yyyymmddhhmmss plus a fraction in billionths). |
| adChapter | 136 | A 4-byte chapter value that identifies rows in a child rowset |
| adPropVariant | 138 | An Automation PROPVARIANT. |
| adVarNumeric | 139 | A numeric value (Parameter object only). |
| adVarChar | 200 | A string value (Parameter object only). |
| adLongVarChar | 201 | A long string value. |
| adVarWChar | 202 | A null-terminated Unicode character string. |
| adLongVarWChar | 203 | A long null-terminated Unicode string value. |
| adVarBinary | 204 | A binary value (Parameter object only). |
| adLongVarBinary | 205 | A long binary value. |
| AdArray | 0x2000 | A flag value combined with another data type constant. Indicates an array of that other data type. |
❮ Tham chiếu đối tượng trường hoàn chỉnh