如果没有，则Dropdownlist绑定null valuee [英] Dropdownlist bound null valuee if there is nothing

问题描述

所以我有问题我在Gridview中有下拉列表首先我需要传递它，如果有人编辑它并给予它值，它将在这里更新是代码片段

So i have question i have dropdownlist in Gridview soo first i need to pass it nothing if someon edit it and gave him value it will update here is code snippet

<asp:DropDownList runat="server" ID="compn" CssClass="Dropdowni" SelectedValue='<%# Bind("Company_ID") %>'

                            DataSourceID="ObjectDataSource5" DataTextField="Name_Ge" 

            DataValueField="Code5" Enabled="false"

 </asp:DropDownList>

'compn' has a SelectedValue which is invalid because it does not exist in the list of items.
Parameter name: value

这是错误给出的错误



我尝试过：

here is the error what it is giving mee

What I have tried:

AppendDataBoundItems="true">
<asp:ListItem Text="Select One" Value=""></asp:ListItem>
</asp:DropDownList>

这里是我试过的但是当我进行编辑时它显示我只在db中选择一个我有一些记录

here is what i have tried but when i go on a edit it is showing me only select one in db i have some records

推荐答案

你需要删除``SelectedValue``属性初始加载。

删除以下内容 -

You need to remove the ``SelectedValue`` property from the initial load.
Remove following-

SelectedValue='<%# Bind("Company_ID") %>'

修改后的代码看起来应该像 - br />

The modified code should looks something like-

<asp:dropdownlist runat="server" id="compn" cssclass="Dropdowni" datasourceid="ObjectDataSource5" datatextfield="Name_Ge" datavaluefield="Code5" enabled="false" xmlns:asp="#unknown">
</asp:dropdownlist>

现在，如果你想要选择的东西，你总是可以在后面的代码中做到这一点。



希望，它有帮助:)

辩诉如果您需要进一步的指导，请告诉我。

Now, if you want something to be selected, you can always do that in code behind.

Hope, it helps :)
Please let me know if you need further guidance on this.

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