小编pos*_*ive的帖子

我有两种方法.首先,我在调用第二个方法时从第一个方法传递一个字符串.在第二种方法中,我做了计算.

现在我想将结果传递回第一个方法.

我如何实现这一目标？

我的代码是这样的:

    private void RegisterButton_Click(object sender, RoutedEventArgs e)
    {

        string databaseName = "databaseName";
            CheckDatabase(databaseName);
            bool test = bRet;
    }
    private bool CheckDatabase(string databaseName)
    {
        string connString = "Server=localhost\\SQLEXPRESS;Integrated Security=SSPI;database=master";
        string cmdText = "select * from master.dbo.sysdatabases where name=\'" + databaseName + "\'";
        bool bRet = false;
        using (SqlConnection sqlConnection = new SqlConnection(connString))
        {
            sqlConnection.Open();
            using (SqlCommand sqlCmd = new SqlCommand(cmdText, sqlConnection))
            {
                int nRet = sqlCmd.ExecuteNonQuery();
                if (nRet <= 0)
                {
                    bRet = false;
                }
                else
                {
                    bRet …

我有这样的代码：

private bool CheckDatabase(string databaseName, bool bRet)
    {
        string connString = "Server=localhost\\SQLEXPRESS;Integrated Security=SSPI;database=master";
        string cmdText = "select * from master.dbo.sysdatabases where name=\'" + databaseName + "\'";



        using (SqlConnection sqlConnection = new SqlConnection(connString))
        {
            sqlConnection.Open();
            using (SqlCommand sqlCmd = new SqlCommand(cmdText, sqlConnection))
            {
                int nRet = sqlCmd.ExecuteNonQuery();
                // regMessage.Text = nRet.ToString();
                if (nRet <= 0)
                {
                    bRet = false;
                }
                else
                {
                    bRet = true;
                }
            }
        }
        return bRet;
    }

然而

nRet

结果总是-1，就好像数据库不存在一样（确实存在）。是不是因为数据库是空的？或者如果创建了数据库，它应该返回> 0，即使它是空的？顺便说一下，字符串 databaseName 是正确的。

EDIT> EDIT：我在“CREATE DATABASE @database”ssql …

我正在尝试使用类Object将新记录添加到SQL数据库表.我创建了一个Products列表,然后用sql语句遍历所有这些产品.

我的代码是这样的:

    private void backupButton_Click(object sender, RoutedEventArgs e)
    {
        ReadAllProductsList dbproducts = new ReadAllProductsList();
        DB_Product = dbproducts.GetAllProducts();
        List<Product> SQLProductList = new List<Product>();
        SQLProductList = DB_Product.Where(Product => Product.UserId == currentUser).ToList();
        for(int i = 0; i < SQLProductList.Count; i++)
        {
            InsertSQLProduct(new Product(SQLProductList[i].UserId,
                                                        SQLProductList[i].Name));

        }
    }

    public void InsertSQLProduct(Product objProduct)
    {
        using (var connection = new SqlConnection("Server=localhost\\SQLEXPRESS;Integrated Security=SSPI;database=MyLocalDB"))
        {
            connection.Open();
            using (SqlCommand command = new SqlCommand("INSERT INTO Product (UserId, Name) '" +
                                                        "'VALUES (null, '" + objProduct.Name + "');", connection))
            {
                command.ExecuteNonQuery();
            } …