Note the type of int problem when inserting a database in insert

For example, a statement, insert into mbproduct (P_USERID,P_BIGID,P_QQ) VALUES ("+getuserid+", "+getdrpdl+" ', "+qq+",, ' "+bb+") (GetUserID is obtained from the primary key, there must be a value, you can write this), if so, suppose that QQ is obtained from the text box, if it is this form:

String Qq=txtqq.text, which occurs when TXTQQ is empty, has no value, that is, insert into mbproduct (P_USERID,P_BIGID,P_QQ) VALUES (1, ' + ', ' AA '), apparently, Syntax error, so, FIX:

Either the SQL statement in QQ, plus single quotation marks, to represent the string, you can convert int type, but not rigorous, or int qq=txtqq.text== ""? 0:int.parse (Txtqq.text), after the type to be judged

Note the type of int problem when inserting a database in insert