c# – 了解ObjectDataSource和选择参数
内容导读
互联网集市收集整理的这篇技术教程文章主要介绍了c# – 了解ObjectDataSource和选择参数,小编现在分享给大家,供广大互联网技能从业者学习和参考。文章包含3781字,纯文字阅读大概需要6分钟。
内容图文
我在GridView控件中有一个TemplateField,如:
<asp:TemplateField ItemStyle-Width="150px">
<ItemTemplate>
<asp:DropDownList ID="ddlFields" runat="server" DataSourceID="odsOperator" DataTextField="Text" DataValueField="Value" />
<asp:HiddenField ID="hfFieldType" runat="server" Value='<%# Eval("FieldType")%>' />
</ItemTemplate>
</asp:TemplateField>
我有一个下拉列表,我想从ObjectDataSource填充,但是对于每一行,我想传递一个Select Parameter,所以它填充了正确的值
<asp:ObjectDataSource ID="odsOperator" runat="server" TypeName="OperatorFieldsDAO"
SelectMethod="FindByType">
<SelectParameters>
<asp:ControlParameter ControlID="hfFieldType" Type="String" Name="Type" PropertyName="Value" />
</SelectParameters>
</asp:ObjectDataSource>
我的OperatorFieldsDAO类是:
public class OperatorFieldsDAO
{
private List<OperatorField> OperatorFields
{
get
{
List<OperatorField> operatorFields = HttpContext.Current.Session["OperatorFields"] as List<OperatorField>;
if (operatorFields == null)
{
operatorFields = new List<OperatorField>();
operatorFields.Add(new OperatorField("string", "contains", "C"));
operatorFields.Add(new OperatorField("string", "begins with", "BW"));
operatorFields.Add(new OperatorField("string", "is equal to", "E"));
operatorFields.Add(new OperatorField("string", "is not equal to", "NE"));
operatorFields.Add(new OperatorField("string", "is less than", "L"));
operatorFields.Add(new OperatorField("string", "is greater than", "G"));
operatorFields.Add(new OperatorField("string", "is less than or equal to", "LE"));
operatorFields.Add(new OperatorField("string", "is greater than or equal to", "GE"));
operatorFields.Add(new OperatorField("string", "is from", "F"));
operatorFields.Add(new OperatorField("string", "is between", "B"));
operatorFields.Add(new OperatorField("string", "is nothing", "N"));
operatorFields.Add(new OperatorField("string", "is something", "S"));
operatorFields.Add(new OperatorField("number", "is the same as", "S"));
operatorFields.Add(new OperatorField("number", "is not the same as", "S"));
operatorFields.Add(new OperatorField("number", "is one of", "S"));
operatorFields.Add(new OperatorField("number", "is not one of", "S"));
operatorFields.Add(new OperatorField("number", "is nothing", "N"));
operatorFields.Add(new OperatorField("number", "is something", "S"));
}
return operatorFields;
}
}
public OperatorFieldsDAO() { }
[DataObjectMethod(DataObjectMethodType.Select)]
public IEnumerable<OperatorField> FindAll()
{
return this.OperatorFields;
}
[DataObjectMethod(DataObjectMethodType.Select)]
public IEnumerable<OperatorField> FindByType(String type)
{
List<OperatorField> r = new List<OperatorField>();
foreach (OperatorField f in this.OperatorFields)
if (f.Type == type)
r.Add(f);
return r;
}
}
所有这些都告诉你我收到了一个错误:
Could not find control ‘hfFieldType’ in ControlParameter ‘Type’.
我究竟做错了什么?
我是否需要使用OnRowDataBound方法以编程方式传递所选参数?
解决方法:
为了使这个工作,我添加创建两个方法(一个用于GridView,另一个用于ObjectDataSource),以及将ControlParameter中的Select Parameter更改为普通参数.
我们的想法是每次创建它时设置参数…
protected void gvSearch_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DropDownList d = (DropDownList)e.Row.FindControl("ddlFields");
string type = ((HiddenField)e.Row.FindControl("hfFieldType")).Value;
_type = type;
d.DataBind();
}
}
protected void odsOperator_Selecting(object sender, ObjectDataSourceSelectingEventArgs e)
{
e.InputParameters["Type"] = _type;
}
private string _type = "";
而ObjectDataSource将是
<asp:ObjectDataSource ID="odsOperator" runat="server" TypeName="OperatorFieldsDAO"
SelectMethod="FindByType" onselecting="odsOperator_Selecting">
<SelectParameters>
<asp:Parameter Type="String" Name="Type" />
</SelectParameters>
</asp:ObjectDataSource>
我希望它可以帮助任何人……
内容总结
以上是互联网集市为您收集整理的c# – 了解ObjectDataSource和选择参数全部内容,希望文章能够帮你解决c# – 了解ObjectDataSource和选择参数所遇到的程序开发问题。 如果觉得互联网集市技术教程内容还不错,欢迎将互联网集市网站推荐给程序员好友。
内容备注
版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 gblab@vip.qq.com 举报,一经查实,本站将立刻删除。
内容手机端
扫描二维码推送至手机访问。