There are several queries to be performed which return the DataTable object. In order to speed up the development I created a private method which should return the dataset by taking the query string as an argument.
the method is the following:
private DataTable getDataTable(string query)
    {
        DataTable dt = new DataTable();
        SqlDataAdapter DA = new SqlDataAdapter(query, conn);
        try
 开发者_StackOverflow       {
            iStatusIndicator.SetBusy(true);
            iStatusIndicator.SetStatus("executing query" + query);
            DA.Fill(dt);
        }
        catch (Exception ex)
        {
            ...
        }
        iStatusIndicator.SetBusy(false);
        iStatusIndicator.SetStatus("");
        return dt;
    }
the procedure doesn't throw an exception but the DataTable dt is always null. I tried to run a query string directly in sql command prompt and it returns the data as expected so I don't know what could be the problem.
I would be very thankful if anyone of you explained the cause, suggested a fix or a better method for returning DataTables by receiving query strings.
Thank you
private static DataSet SelectRows(DataSet dataset,
    string connectionString,string queryString) 
{
    using (SqlConnection connection = 
        new SqlConnection(connectionString))
    {
        SqlDataAdapter adapter = new SqlDataAdapter();
        adapter.SelectCommand = new SqlCommand(
            queryString, connection);
        adapter.Fill(dataset);
        return dataset;
    }
}
What's in your catch block? By any chance is there something that does a return or exit sub? That seems to be the only way that I can see that this function would return NOthing (Ie. Your function is not ever reaching the "return dt;" line
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                        
 加载中,请稍侯......
      
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