Question

过滤器适用于myTicketsSubmitButton但不适用于allTicketsSubmitButton。代码是相同的，但我不明白为什么它适用于一种方法而不是另一种方法。

我在Visual Studio 2010中使用WinForms和C＃

    private void myTicketsSubmitButton_Click(object sender, EventArgs e)
    {
        String sqlQuery = "SELECT u.CallerName, t.* FROM users u INNER JOIN tickets t ON u.id = t.user WHERE u.CallerName = '" + Environment.UserName.ToLower() + "'";
        GetData(sqlQuery);

        if (myTicketsAllRadioButton.Checked)
        {
            //GetData(sqlQuery);
            ticketsBindingSource.Filter = "ProblemStatus LIKE '%'";
        }

        if (myTicketsClosedRadioButton.Checked)
        {
            //GetData(sqlQuery);
            ticketsBindingSource.Filter = "ProblemStatus = 'Closed'";
        }

        if (myTicketsOpenRadioButton.Checked)
        {
            //GetData(sqlQuery);
            ticketsBindingSource.Filter = "ProblemStatus = 'Open'";                
        }
    }

    private void allTicketsSubmitButton_Click(object sender, EventArgs e)
    {
        String sqlQuery = "SELECT u.CallerName, t.* FROM users u INNER JOIN tickets t ON u.id = t.user";
        GetData(sqlQuery);

        if (myTicketsAllRadioButton.Checked)
        {
            //GetData(sqlQuery);
            ticketsBindingSource.Filter = "ProblemStatus LIKE '%'";
        }

        if (myTicketsClosedRadioButton.Checked)
        {
            //GetData(sqlQuery);
            ticketsBindingSource.Filter = "ProblemStatus = 'Closed'";
        }

        if (myTicketsOpenRadioButton.Checked)
        {
            //GetData(sqlQuery);
            ticketsBindingSource.Filter = "ProblemStatus = 'Open'";               
        }
    }

    private void GetData(string selectCommand) 
    {
        OleDbDataAdapter dataAdapter = new OleDbDataAdapter();
        BindingSource bindingSource1 = new BindingSource();
        try 
        {
            // Specify a connection string. Replace the given value with a  
            // valid connection string for a Northwind SQL Server sample 
            // database accessible to your system.
            String connectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\Users\\testdb.accdb";

            // Create a new data adapter based on the specified query. 
            dataAdapter = new OleDbDataAdapter(selectCommand, connectionString);

            // Create a command builder to generate SQL update, insert, and 
            // delete commands based on selectCommand. These are used to 
            // update the database. 
            OleDbCommandBuilder commandBuilder = new OleDbCommandBuilder(dataAdapter);

            // Populate a new data table and bind it to the BindingSource. 
            DataTable table = new DataTable(); 
            table.Locale = System.Globalization.CultureInfo.InvariantCulture; 
            dataAdapter.Fill(table); 
            bindingSource1.DataSource = table;
            ticketsBindingSource = bindingSource1;

            // Resize the DataGridView columns to fit the newly loaded content. 
            //ticketsDataGridView.AutoResizeColumns(DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader);                

            ticketsDataGridView.DataSource = bindingSource1;
        }
        catch(OleDbException)
        {
            MessageBox.Show("To run this example, replace the value of the connectionString variable with a connection string that is valid for your system.");
        }
    }

我有6个单选按钮。

其中3个是myTickets - 打开 - 关闭 - 所有

其中3个适用于所有门票 - 打开 - 关闭 - 所有

单击myTickets组的单选按钮时，一切正常

我对代码做了一些小改动，但是allTicketsSubmitButton没有显示Open或All门票的所有门票。

数据库相对较小，所以我可以随时快速测试。

我有5个条目 2打开 2关闭 1正在进行中

2个条目被分配给另一个用户（因此其中3个是myTickets）。

我发现了一些奇怪的东西

如果我将myTickets和allTickets的单选按钮设置为相同的东西，结果只能正确显示

（两个打开都会显示打开的门票）如果一个是开放的而另一个是关闭的，则没有任何反应

Answer 1

如果您有6个单选按钮，3个用于myTickets，3个用于allTickets，那么为什么要在allTickets按钮单击事件下检查myTickets？

我认为您需要更改代码：

private void allTicketsSubmitButton_Click(object sender, EventArgs e)
    {
        String sqlQuery = "SELECT u.CallerName, t.* FROM users u INNER JOIN tickets t ON u.id = t.user";

        if (myTicketsAllRadioButton.Checked)
        {
            GetData(sqlQuery);
            ticketsBindingSource.Filter = "ProblemStatus LIKE '%'";
        }

        if (myTicketsClosedRadioButton.Checked)
        {
            GetData(sqlQuery);
            ticketsBindingSource.Filter = "ProblemStatus = 'Closed'";
        }

        if (myTicketsOpenRadioButton.Checked)
        {
            GetData(sqlQuery);
            ticketsBindingSource.Filter = "ProblemStatus = 'Open'";               
        }
    }

TO：

private void allTicketsSubmitButton_Click(object sender, EventArgs e)
    {
        String sqlQuery = "SELECT u.CallerName, t.* FROM users u INNER JOIN tickets t ON u.id = t.user";
        GetData(sqlQuery); // move this here, you only need this in one place

        if (allTicketsAllRadioButton.Checked)
        {
            ticketsBindingSource.Filter = "ProblemStatus LIKE '%'";
        }

        if (allTicketsClosedRadioButton.Checked)
        {
            ticketsBindingSource.Filter = "ProblemStatus = 'Closed'";
        }

        if (allTicketsOpenRadioButton.Checked)
        {
            ticketsBindingSource.Filter = "ProblemStatus = 'Open'";               
        }
    }

BindingSource过滤器无法正常工作

1 个答案: