如何使用"读取更多"链接限制GridView中的标签字符串长度？

Question

目前我这样使用......

<asp:TemplateField HeaderText="Description">
 <ItemTemplate>
      <asp:Label ID="lblDescription" runat="server"
                Text='<%# Limit(Eval("Description"),40) %>' >
      </asp:Label>
 </ItemTemplate>

辅助函数:

public static string Limit(object Desc, int length)
{
    StringBuilder strDesc = new StringBuilder();
    strDesc.Insert(0, Desc.ToString());

    if (strDesc.Length > length)
        return strDesc.ToString().Substring(0, length) + "..." + [Read More];
    else return strDesc.ToString();
}

但我不知道如何把[阅读更多]链接...

Answer 1

做这样的事情.

标记

<asp:TemplateField HeaderText="Description">
 <ItemTemplate>
      <asp:Label ID="lblDescription" runat="server"
                Text='<%# Limit(Eval("Description"),40) %>' 
                Tooltip='<%# Eval("Description") %>'>
      </asp:Label>
      <asp:LinkButton ID="ReadMoreLinkButton" runat="server"
                Text="Read More"
                Visible='<%# SetVisibility(Eval("Description"), 40) %>'
                OnClick="ReadMoreLinkButton_Click">
      </asp:LinkButton>
 </ItemTemplate>
</asp:TemplateField>

代码隐藏

protected bool SetVisibility(object desc, int maxLength)
{
    var description = (string)desc;
    if (string.IsNullOrEmpty(description)) { return false; }
    return description.Length > maxLength;
}

protected void ReadMoreLinkButton_Click(object sender, EventArgs e)
{
    LinkButton button = (LinkButton)sender;
    GridViewRow row = button.NamingContainer as GridViewRow;
    Label descLabel = row.FindControl("lblDescription") as Label;
    button.Text = (button.Text == "Read More") ? "Hide" : "Read More";
    string temp = descLabel.Text;
    descLabel.Text = descLabel.ToolTip;
    descLabel.ToolTip = temp;
}

protected string Limit(object desc, int maxLength)
{
    var description = (string)desc;
    if (string.IsNullOrEmpty(description)) { return description; }
    return description.Length <= maxLength ? 
        description : description.Substring(0, maxLength)+ "...";
}