由网友(孤單的背影﹎)分享简介：我有两个的DropDownList和一个按钮。我使用断点在我的项目，一切工作正常。但是，一旦我得到了这个按钮的功能是我得到的错误：I have two dropdownlist and a button. I used the breakpoint in my project and everything is wo...

我有两个的DropDownList和一个按钮。我使用断点在我的项目，一切工作正常。但是，一旦我得到了这个按钮的功能是我得到的错误：

I have two dropdownlist and a button. I used the breakpoint in my project and everything is working fine. But as soon I am getting out of the function of the button this is the error I am getting:

能不能在DropDownList中选择多个项目。

"Cannot have multiple items selected in a DropDownList."

下面是我的code到该按钮：

Here is my code to that button:

 protected void Button1_Click(object sender, EventArgs e)
    {

        if (ddlPlayer1.SelectedItem.Value != "0" || ddlPlayer2.SelectedItem.Value != "0" && ddlPlayer1.SelectedItem.Value != ddlPlayer2.SelectedItem.Value)
        {
            lblPlayer1Score.Text = Repository.Instance.ReturnScore(ddlPlayer1.SelectedValue.ToString(), ddlPlayer2.SelectedValue.ToString()).Rows[0][0].ToString();
            lblPlayer2Score.Text = Repository.Instance.ReturnScore(ddlPlayer2.SelectedValue.ToString(), ddlPlayer1.SelectedValue.ToString()).Rows[0][0].ToString();


        }

        ddlPlayer1.DataBind();
        ddlPlayer2.DataBind();
    }

我在做什么错在这里？ ：（

What I am doing wrong here? :(

推荐答案

请确保你没有数据绑定的DDL多次到同一个数据源。 被选择为项的属性，因此，如果不同的DDL 选择同一数据源不同的项目，每个项目中的DDL的结束 与选定的多个项目这可能是这里发生了什么。

Make sure you are not databinding multiple ddls to the same datasource. Being selected is an attribute of an item, therefore, if different ddls select different items from the same datasource, each of the ddls ends up with multiple items selected which is probably what is happening here..