VB+SQL语句事例代码(国外英文资料).doc

VB+SQL语句事例代码(国外英文资料) Specific code for VB design -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- One. Required classes [Students] / / Students -- -- -- -- -- -- -- - Member functions (specific function implementation and parameter omission) Init / / uncommented is similar to the above, not to mention The Delete GetInfo GetName GetNewld The Insert Load_By_Class / / reads all the student Numbers in the specified class to the array Arr_StuId () and Arr_StuName () The Update Update_Transfer / / changes the class information Class_Id for the student, which is used when the class is switched Load_By_Class concrete implementation: { The Pulic Sub Load_By_Class (By Val TempClassId As Integer) Dim I As Integer / / initialize the class array Erase Arr_StuId/Erase statement reinitializes the element of the fixed array and the storage space for the dynamic array ReDim Arr_StuId (0) / / ReDim redistributes storage space for array variables Erase Arr_StuName ReDim Arr_StuName (0) DB_Connect / / connection database SqlStmt = SELECT Student_Id, Student_Name FROM Students WHERE Class_Id - + Trim (TmpClassId) + ORDER BY Student_Id / / to execute the SQL statement The effect of Trim in / / VB is to remove the Spaces in the string, for example, here Remove the whitespace from the string TmpClassId and assign it to Class_Id. OdbcExt (SqlStmt) / / execute SQL statements I = 0 The function of the Do Unitil SQLFetch (Hstmt) = SQL_NO_DATA_FOUND / / SQLFetch function will be The current record pointer for the result set moves to the next record ColVa = String (40, 0) Rc = SQLGetData (Hstmt, 1, 1, ColVal, Len (ColVal), pcblen) ReDim Preserve Arr_StuId (I + 1) Arr_StuId (I) = Val (ColVal) ColVal = String (40, 0) Rc = SQLGetData