数据类型的处理(提取自FMDB)

if ((!obj) || ((NSNull *)obj == [NSNull null])) {

        sqlite3_bind_null(pStmt, idx);

    }

    

    // FIXME - someday check the return codes on these binds.

    else if ([obj isKindOfClass:[NSData class]]) {

        const void *bytes = [obj bytes];

        if (!bytes) {

            // it's an empty NSData object, aka [NSData data].

            // Don't pass a NULL pointer, or sqlite will bind a SQL null instead of a blob.

            bytes = "";

        }

        sqlite3_bind_blob(pStmt, idx, bytes, (int)[obj length], SQLITE_STATIC);

    }

    else if ([obj isKindOfClass:[NSDate class]]) {

        if (self.hasDateFormatter)

            sqlite3_bind_text(pStmt, idx, [[self stringFromDate:obj] UTF8String], -1, SQLITE_STATIC);

        else

            sqlite3_bind_double(pStmt, idx, [obj timeIntervalSince1970]);

    }

    else if ([obj isKindOfClass:[NSNumber class]]) {

        

        if (strcmp([obj objCType], @encode(BOOL)) == 0) {

            sqlite3_bind_int(pStmt, idx, ([obj boolValue] ? 1 : 0));

        }

        else if (strcmp([obj objCType], @encode(int)) == 0) {

            sqlite3_bind_int64(pStmt, idx, [obj longValue]);

        }

        else if (strcmp([obj objCType], @encode(long)) == 0) {

            sqlite3_bind_int64(pStmt, idx, [obj longValue]);

        }

        else if (strcmp([obj objCType], @encode(long long)) == 0) {

            sqlite3_bind_int64(pStmt, idx, [obj longLongValue]);

        }

        else if (strcmp([obj objCType], @encode(unsigned long long)) == 0) {

            sqlite3_bind_int64(pStmt, idx, (longlong)[obj unsignedLongLongValue]);

        }

        else if (strcmp([obj objCType], @encode(float)) == 0) {

            sqlite3_bind_double(pStmt, idx, [obj floatValue]);

        }

        else if (strcmp([obj objCType], @encode(double)) == 0) {

            sqlite3_bind_double(pStmt, idx, [obj doubleValue]);

        }

        else {

            sqlite3_bind_text(pStmt, idx, [[obj description] UTF8String], -1, SQLITE_STATIC);

        }

    }

    else {

        sqlite3_bind_text(pStmt, idx, [[obj description] UTF8String], -1, SQLITE_STATIC);

    }

原文地址:https://www.cnblogs.com/liyufeng2013/p/3421618.html