dataset

问题 When I open DataSet in Visual Studio 2008 to design or modify it, it always take a very long time (more than five minutes) before I can continue to do my job. While I'm waiting I can't do anything on Visual Studio, moreover CPU and memory usage is growth dramatically. I want to know, Is it has anyway to reduce this waiting time? Hardware - Desktop CPU: Intel Q6600 Memory: 4 GB HDD: 320 GB 7200 rpm OS: Windows XP 32 bit with Service Pack 3 回答1: Have you tried this? Go to the Options -> Windows

问题 Ok so I'm trying to use the JavaScriptSerializer to work with this code. However it crashes when it reaches the last line; Dim json As New String(sr.Serialize(dt)) I get this error message; A circular reference was detected while serializing an object of type 'System.Reflection.Module'. I would really appreciate any insights that could help solve this problem. 回答1: Circular reference means that serialising the object would result in an infinite loop. For example if you would try to serialize

问题 I am getting a date time field from database with timestamp. My grid has an auto-generated column. I am formatting it in my .cs page dsWorkItems.Tables[0].Rows[count]["Date"] = !string.IsNullOrEmpty(dsWorkItems.Tables[0].Rows[count]["Date"].ToString()) ? ((DateTime)(dsWorkItems.Tables[0].Rows[count]["Date"])).ToShortDateString(): ""; In quick watch I am getting ((DateTime)(dsWorkItems.Tables[0].Rows[count]["Date"])).ToShortDateString() as 9/26/2013 but in grid I am getting 9/26/2013 12:00:00

问题 We're working with a DataGridView bound to a database. We are trying to have one of the columns calculated as an average of some of the other columns from the database. We were unable to create a computed column in the database nor were we successful in creating one in the dataset. If there's a way to do this, our problem is solved. Ex: AvgSkill = Avg(Skill1, Skill2, Skill3) Since we can't seem to create a computed column, we tried creating a cell event handler that would calculate the new

问题 Is it possible to use the 'DataTable' or 'DataSet' classes in ASP vNext Core 5.0? When I try to use those classes, I am getting the error: 'The type or namespace name 'DataTable' could not be found'. 回答1: This question is a few months old but I see it coming up all the time so I'll post an answer. As of beta 3, aspnetcore contains only a subset of the System.Data related members, which can be referenced in System.Data.SqlClient, and System.Data.Common. Among the more noticeable items missing

问题 Hi there I am looking to combine two data ranges/arrays into one in order to feed them into excel FREQUENCY function. Example: First data range - B5:F50 Second data range - J5:N50 Bins data range - I5:I16 Function definition - FREQUENCY(data_array; bins_array) Basically I am lazy and I don't want to reshuffle my excel script to spit out both datasets side by side so that I can reference them using something like B5:K50 range. Is there any way I can combine both datasets into data_array using

问题 For teaching purposes, I need to generate random datasets of correlated random variables with different distributions. I have tried corr2data in Stata but it will not allow me to specify max and min values of the variables to be generated, just means, sd's and the covariance matrix. Therefore, I need to do messy adjustments after generation of the data. Various other details annoy me with corr2data . Is there a simpler way of doing this with MATLAB? I am not as familiar with this software as

问题 using a dataset,each row has a method called hasVersion() which implies to me it keeps a copy of the original and current versions of that row. How can I get one of the original row values? I'd imagine it's possible to call reject changes on that row and then check the value, but I'd rather not lose the changes, just read the value(s). 回答1: If you are looking at a particular row, you can get a particular version of the row's values through the DataRowVersion enumeration thru one of the

问题 I am using asp.net 2.0 and c#. I have a dataset, which is getting the employee info. Now I want to filter the gridview based on a name that the user has put in the search textbox. I am doing this: DataSet ds = new DataSet("EmployeeInformation"); //........ loading DataSet ds with emploee info string strExpr; strExpr = "Name LIKE %" + txtSearchEmployee.Text.Trim() + "%"; ds.Tables[0].Select(strExpr); I am getting an error in the last step, that the operator is missing. Please guide me how can

问题 I am working on a project that relies on DataSet and DataTable. We wish to move into cross platform so are looking at Portable Class Libraries. However we cant find out how to use DataSet and DataTable in a portable class library. Are they available? Maybe we should be moving away from DataSets and DataTables but we have what we have right now. 回答1: No the Dataset and DataTable are quite Windows specific Data structures, they would not be cross compatible, you may instead plan to serialize