将事件格式应用于所有文本框

Question

我已经写了这段代码：

private void maskedNASC_KeyDown(object sender, KeyEventArgs e)
{  
    maskedNASC.BackColor = Color.Aqua;
}

private void maskedNASC_Leave(object sender, EventArgs e)
{  
    maskedNASC.BackColor = Color.White;
}

我想将此属性应用于表单的所有文本框和屏蔽文本。

我见过很多这样的代码：

void SetProperty(Control ctr) // resalta textbox onfocus
{
    foreach (Control control in ctr.Controls)
    {
        if (control is TextBox)
        {
            control.Leave == control.BackColor = Color.Aqua;
            control.KeyDown += BackColor = Color.White ;
        }
    }
}

写这个的正确方法是什么？？

谢谢。亚历杭德罗。

我已将此添加到 form1.designer 中：

this.maskedNASC.Leave += TextBoxEvent_Leave;
this.maskedNASC.KeyDown += TextBox_KeyDown;

但是下面的代码有错误

 [![enter image description here][1]][1]

Answer 1

你可以这样写

void SetProperty(Control ctr) // resalta textbox onfocus
{
    foreach (Control control in ctr.Controls)
    {
        if (control is TextBox)
        {
            control.Leave -= control_Leave; //Remove control_Leave if already binded. 
            control.Leave += control_Leave; //Assigne control_Leave 
            control.KeyDown -= control_KeyDown ; //Remove control_KeyDown if already binded. 
            control.KeyDown += control_KeyDown ; //Assigne control_KeyDown 
        }
    }
}



private void control_Leave(object sender, EventArgs e)
{
   ((Control)sender).BackColor = Color.Aqua;
}

private void control_KeyDown(object sender, KeyEventArgs e)
{
   ((Control)sender).BackColor = Color.White;
}

Answer 2

例如，您可以使事件更通用（使用 C# 8.0 中的模式匹配）

    private void TextBoxEvent_Leave(object sender, EventArgs e)
    {
        if (sender is TextBox bx)
        {
            bx.BackColor = Color.White;
        }
    }

    private void TextBox_KeyDown(object sender, EventArgs e)
    {
        if (sender is TextBox bx)
        {
            bx.BackColor = Color.Red;
        }
    }

在构造函数中添加

        this.maskedNASC.Leave += TextBoxEvent_Leave;
        this.maskedNASC.KeyDown += TextBox_KeyDown;

对于您拥有的每个文本框

您也可以根据您使用的 C# 版本尝试以下操作

    private void TextBoxEvent_Leave(object sender, EventArgs e)
    {
        if (sender is TextBox)
        {
            ((TextBox)sender).BackColor = Color.White;
        }
    }

    private void TextBox_KeyDown(object sender, EventArgs e)
    {
        if (sender is TextBox)
        {
            ((TextBox)sender).BackColor = Color.Red;
        }
    }