Question

<img src ="~/UserControls/Vote/Images/Arrow Up.png" id = "vote-up-off" 
        runat = "server" alt ="vote up" 
class="voteupImage" style="height: 45px; width: 44px"/>

这里我想改变某些条件的图像的src，如

if ( a==4)
{
src  url  shuld be ......
}
else
{ 
src  url should be...
}

Answer 1

首先，您需要提供一个id名称，该名称可用作变量：

<img src="~/UserControls/Vote/Images/Arrow Up.png" 
     id="VoteUpOff" 
     runat="server" alt ="vote up" 
     class="voteupImage" 
     style="height: 45px; width: 44px"
/>

在您的代码中，您可以使用此变量：

if (someCondition)
{
    VoteUpOff.Attributes["src"] = ResolveUrl("~/UserControls/foo.png");
}

Answer 2

您需要将ID更改为不带连字符的内容，但它会是

voteUpOff.Attributes["src"] = "myImage.png";

Answer 3

HTML

<img src="~/UserControls/Vote/Images/Arrow Up.png" 
         id="VoteUpOff" 
         runat="server" alt ="vote up" 
         class="voteupImage" 
         style="height: 45px; width: 44px"
    />

服务器端

if (someCondition) { VoteUpOff.Attributes["src"] = ResolveUrl("~/UserControls/foo.png"); }

请记住，要查看更改，您必须在UpdatePanel中放置“img”执行更改后更新UpdatePanel，如果其UpdateMode = Conditional，否则如果其属性ChildAsTriggers = True，它将自动更新

Answer 4

试试这个，它为我工作

<img src="_images/<%= AssignImageURL() %>" alt="Logo" />

C＃方法

protected string AssignImageURL()
{
    String ID = Convert.ToString(Session["id"]);
    ds = sq.SelectQuery("Select LogoURl from table where ID='"+ ID+"' ");
    if (Convert.ToString(ds.Tables[0].Rows[0][0]).Trim() != "")
        return Convert.ToString(ds.Tables[0].Rows[0][0]).Trim();
    else
        return "Logo.jpg";
}

Answer 5

if (someCondition)
{
    vote-up-off.Attributes["src"] = ResolveUrl("~/UserControls/pic.png");
}

如何用c＃更改html图像src

5 个答案: