Question

对于我处理图形的应用程序，我已经设置了一个小的DialogBox：

最大;
敏;
主要步骤（比例尺）;
小步骤。

这是一个截屏：

enter image description here

我想在允许用户点击 Ok 之前验证一些内容：

Max＆gt; = Min
MaxScale＆gt; = MinScale。

但它没有像我一样工作：如果我设置Min＆gt; Max，文本框为红色但 Ok 按钮仍然启用...

我该如何解决？

这是我的代码：

public partial class AxisPropertiesDial : Form
{
    public AxisPropertiesDial(string title, double max, double min, double majorStep, double minorStep)
    {
        Max = max;
        Min = min;
        MajorStep = majorStep;
        MinorStep = minorStep;
        InitializeComponent();

        tbMax.Text = max.ToString();
        tbMin.Text = min.ToString();
        tbMajStep.Text = majorStep.ToString();
        tbMinStep.Text = minorStep.ToString();
        Load += OnLoad;
        Text = "Axis: " + title;
    }

    private void OnLoad(object sender, EventArgs e)
    {
        SetDesktopLocation(Cursor.Position.X - Size.Width / 2, Cursor.Position.Y - Size.Height / 2);
    }

    public double Max;
    public double Min;
    public double MajorStep;
    public double MinorStep;

    private void btnOk_Click(object sender, EventArgs e)
    {
        Max = Convert.ToDouble(tbMax.Text);
        Min = Convert.ToDouble(tbMin.Text);
        MajorStep = Convert.ToDouble(tbMajStep.Text);
        MinorStep = Convert.ToDouble(tbMinStep.Text);
    }

    private void ValidateTextBox(TextBox tb, double save, out double valueToAssign, double compareTo, bool greaterThan)
    {
        btnOk.Enabled = false;
        tb.BackColor = Color.Tomato;
        if (!Double.TryParse(tb.Text, out valueToAssign))
        {
            valueToAssign = save;
            return;
        }
        if (greaterThan && (valueToAssign >= compareTo) || !greaterThan && (valueToAssign <= compareTo))
        {
            btnOk.Enabled = true;
            tb.BackColor = Color.White;
        }
        else
        {
            //Rollback
            valueToAssign = save;
        }
    }

    private void ValidateAll()
    {
        ValidateTextBox(tbMax, Max, out Max, Min, true);
        ValidateTextBox(tbMin, Min, out Min, Max, false);
        ValidateTextBox(tbMajStep, MajorStep, out MajorStep, MinorStep, true);
        ValidateTextBox(tbMinStep, MinorStep, out MinorStep, MajorStep, false);
    }

    private void tb_TextChanged(object sender, EventArgs e)
    {
        ValidateAll();
    }
}

Answer 1

问题是你在检查单个文本框时尝试启用或禁用按钮，并且它们彼此冲突，而逻辑需要处于更高级别。更改文本框验证功能以返回bool，并在ValidateAll中使用该功能确定是否启用该按钮：

private bool ValidateTextBox(TextBox tb, double save, out double valueToAssign, double compareTo, bool greaterThan)
{
    tb.BackColor = Color.Tomato;
    if (!Double.TryParse(tb.Text, out valueToAssign))
    {
        valueToAssign = save;
        return false;
    }
    if (greaterThan && (valueToAssign >= compareTo) || !greaterThan && (valueToAssign <= compareTo))
    {
        tb.BackColor = Color.White;
        return true;
    }
    else
    {
        //Rollback
        valueToAssign = save;
        return false;
    }
}

private void ValidateAll()
{
    btnOk.Enabled = 
        ValidateTextBox(tbMax, Max, out Max, Min, true) &
        ValidateTextBox(tbMin, Min, out Min, Max, false) &
        ValidateTextBox(tbMajStep, MajorStep, out MajorStep, MinorStep, true) &
        ValidateTextBox(tbMinStep, MinorStep, out MinorStep, MajorStep, false);
}

带有值验证的DialogBox

1 个答案: