Question

我有一个div标签，我只想在函数返回true时更改，否则我希望它保持相同的内容。我使用render: nothing => true但删除了所有内容。

<%= javascript_include_tag :defaults %> 
<div id="x">Hi</div>
<% form_remote_tag :url => {:action => 'get'},
    :update => 'x' do %>
<%= text_field_tag 'url' %>
<%= submit_tag "Submit" %>
<% end %>



def getImage
    @img = params[:url]
    if !verify @img
        render :nothing => true
    end
end
private
def verify url
    return true if url =~ /https?:\/\/.*\.(jpg|png|gif|bmp)$/
    return false
end

我想让我的rails代码执行此操作

var lastrequest = "";

function ajaxObj() { //Returns the ajax object based on browser
    if ( window.XMLHttpRequest ) {
        return new XMLHttpRequest(); //Firefox
    } else if ( window.ActiveXObject ) {
        return new ActiveXObject("Microsoft.XMLHTTP"); //IE
    }
}

window.onload = function() {
    document.getElementById("Submit").onclick = function() { 
        var request = ajaxObj();

        request.onreadystatechange = function() { 
            if ( request.readyState == 4 ) { 
                document.getElementById("imgdisplay").innerHTML = request.responseText; 
                document.getElementById("imgurl").value = "";
            }
        }

        if ( lastrequest != document.getElementById("imgurl").value ) { // Makes sure it doesn't request the same image twice
            var parameters = "url=" + document.getElementById("imgurl").value;

            request.open("POST", "imageget.php", true); // Sends the ajax request
            request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
            request.setRequestHeader("Content-length", parameters.length);
            request.setRequestHeader("Connection", "close");
            request.send(parameters);

            lastrequest = document.getElementById("imgurl").value;
        }
    }
}

Answer 1

使用状态代码或无法控制发生的情况。 http://api.rubyonrails.org/classes/ActionView/Helpers/PrototypeHelper.html#M001645

Answer 2

您还可以使用控制器中的代码删除:update => 'x'部分：

def getImage
        @img = params[:url]
        if !verify @img
                render :nothing => true
        else
                render :update do |page|
                    page['x'].replace_html :partial => <some partial here>
                end
        end
end

或者，有点简短：

def getImage
        @img = params[:url]
        render :update do |page|
            page['x'].replace_html(:partial => <some partial here>) if verify(@img)
        end
end

迎接

Rails保持为false，如果为true则呈现

2 个答案: