C# 在新的 gridview 1-1 关系中显示选定的行数据

Question

I'm creating a simple Patient App. 1-1 relationship between patient and medical history record. When the app is started the patient are displayed. When one patient is selected and the button is clicked, the medical history for that patient should be displayed.

My problem is all medical history is being displayed rather than that particular patient.

          private void PopulateGrid()
    {
        var records = _db.GeneralMedicalHistories.Select(q => new
        {
            PatientNumber = q.GeneralMedicalHistoryID,
            MaritalStatus = q.MartialStatus,
            Education = q.Education,
            BloodType = q.BloodType,
            Pregenancies = q.Pregnancies,
            Tobacco = q.Tobacco,
            Alcohol = q.Alcohol,
            Drug = q.Drug,
            MedicalHistoryNotes = q.MedicalHistoryNotes,

        }).ToList();

        gvDemographics.DataSource = records;
        gvDemographics.Columns["PatientNumber"].HeaderText = "Patient#";
        gvDemographics.Columns["MaritalStatus"].HeaderText = "Marital Status";
        gvDemographics.Columns["BloodType"].HeaderText = "Blood Type";
        gvDemographics.Columns["MedicalHistoryNotes"].HeaderText = "Medical History Notes";
        //Hide the column for ID. Changed from the hard coded column value to the name, 
        // to make it more dynamic. 
        gvDemographics.Columns["PatientNumber"].Visible = true;
    }

    

Answer 1

You've selected the elements that you want to display in your gridview, but you have not set any sort of criteria for filtering the results of your query. To do this, first obtain the ID associated with the record that you want to display, I'll call it patientID . Adding the .Where(PatientNumber = patientID) extension method to your query should filter your results to just the patient with that patientID .

.Where() documentation.