c# - 我怎样才能使这段代码更优化

Question

我如何优化这段代码？我不喜欢 case 语句，有什么方法可以改进这段代码吗？

protected void ddlFilterResultBy_SelectedIndexChanged(object sender, EventArgs e)
{ 
    string selVal = ddlFilterResultBy.SelectedValue.ToString().ToLower();

    switch (selVal)
    {
        case "date":
            pnlDate.Visible = true; 
            pnlSubject.Visible = false;
            pnlofficer.Visible = false;
            pnlCIA.Visible = false;
            pnlMedia.Visible = false;
            pnlStatus.Visible = false;                    
            break;

        case "subject":
            pnlDate.Visible = false;
            pnlSubject.Visible = true;
            pnlofficer.Visible = false;
            pnlCIA.Visible = false;
            pnlMedia.Visible = false;
            pnlStatus.Visible = false;
            break;

        case "officer":
            pnlDate.Visible = false;
            pnlSubject.Visible = false;
            pnlofficer.Visible = true;
            pnlCIA.Visible = false;
            pnlMedia.Visible = false;
            pnlStatus.Visible = false;
            break;

        case "status":
            pnlDate.Visible = false;
            pnlSubject.Visible = false;
            pnlofficer.Visible = false;
            pnlCIA.Visible = false;
            pnlMedia.Visible = false;
            pnlStatus.Visible = true;
            break;

        default:
            pnlDate.Visible = false;
            pnlSubject.Visible = false;
            pnlofficer.Visible = false;
            pnlCIA.Visible = false;
            pnlMedia.Visible = false;
            pnlStatus.Visible = false;
            break;
    }
}

Answer 1

很简单。根据大小写选项，您只能使一项可见，因此只需按如下方式设置可见性:

pnlDate.Visible = (selVal == "date"); 
pnlSubject.Visible = (selVal == "subject");
pnlofficer.Visible = (selVal == "officer");
pnlCIA.Visible = false;
pnlMedia.Visible = false;
pnlStatus.Visible = (selVal == "status");    

这比将所有内容都设置为 visible = false; 然后只显示您需要的项目要好，因为这只包含 6 行代码以进行实际的可见性设置。