System.Runtime.InteropServices.SEHException，C ++ / CLI

Question

我确定代码是正确的。我在C ++ / CLI环境中从database.h执行调用方法 在执行期间，执行 SQL select语句的行遇到System.Runtime.InteropServices.SEHException，外部组件抛出了异常。

这是C ++环境 database.h

int SQLconn::displayData(string model) {
    int count;
    if (con == NULL) {
        cout << "Please setup connection first!";
        system("Pause");
    }else {
        stmt = con->createStatement();
        res = stmt->executeQuery("SELECT Model, COUNT(*) FROM database WHERE Model = '" + model + "'");

        while (res->next()) {
        count = res->getInt("COUNT(*)");
        int total = Convert::ToInt32(count);
        return total;
        }
    }
};

这是C ++ / CLI环境

SQLConn sqlConn;
int sam = sqlConn.displayData("Broom");
                String^ SamCount = sam.ToString();
                this->chart2->Series["occurenceCount"]->Points->AddXY("Broom", SamCount);