Can I use conditional statements with EJS templates (in JMVC)?

问题

and if yes, what is the syntax? My goal is to prepend an \'s\' to the word \'comment\' when there is more than one. in an jQuery.ejs template in a JMVC app. The following breaks. I can\'t find any docs for conditionals...

<%=commentsNumber%> comment<% if (commentsNumber > 1) { %> s <% } %>

回答1:

For others that stumble on this, you can also use ejs params/props in conditional statements:

recipes.js File:

app.get("/recipes", function(req, res) {
    res.render("recipes.ejs", {
        recipes: recipes
    });
});

recipes.ejs File:

<%if (recipes.length > 0) { %>
// Do something with more than 1 recipe
<% } %>

回答2:

Conditionals work if they're structured correctly, I ran into this issue and figured it out.

For conditionals, the tag before else has to be paired with the end tag of the previous if otherwise the statements will evaluate separately and produce an error.

ERROR!

<% if(true){ %>
   <h1>foo</h1>
<% } %>
<% else{ %>
   <h1>bar</h1>
 <% } %>

Correct

<% if(true){ %>
   <h1>foo</h1>
 <% } else{ %>  
   <h1>bar</h1>
<% } %>

hope this helped.

回答3:

EJS seems to behave differently depending on whether you use { } notation or not:

I have checked and the following condition is evaluated as you would expect:

<%if (3==3) {%>  TEXT PRINTED  <%}%>
<%if (3==4) {%>  TEXT NOT PRINTED  <%}%>

while this one doesn't:

<%if (3==3) %>  TEXT PRINTED  <% %>
<%if (3==4) %>  TEXT PRINTED  <% %>

回答4:

Yes , You can use conditional statement with EJS like if else , ternary operator or even switch case also

For Example

Ternary operator : <%- role == 'Admin' ? 'Super Admin' : role == 'subAdmin' ? 'Sub Admin' : role %>

Switch Case

<% switch (role) {
case 'Admin' : %>
        Super Admin
        <% break;

case 'eventAdmin' : %>
        Event Admin
        <% break;

case 'subAdmin' : %>
        Sub Admin
        <% break;

} %>

回答5:

You can also use else if syntax:

<% if (x === 1) { %>
    <p>Hello world!</p>
<% } else if (x === 2) { %>
    <p>Hi earth!</p>
<% } else { %>
    <p>Hey terra!</p>
<% } %>

来源：https://stackoverflow.com/questions/8216918/can-i-use-conditional-statements-with-ejs-templates-in-jmvc

标签

conditional-statements

ejs