OGNL Syntax Issue

问题

I have a Struts 2 JSP page with the following snippet:

<s:property value="%{myVariable}" />

which correctly prints out the value of myVariable.

Now, I want to pass myVariable to a method in my action that computes a result based on the value of myVariable. I tried the following:

<s:property value="%{myMethod(myVariable)}" />

The first line in myMethod prints out a debug statement. With the above snippet, this debug statement was not printed.

I then tried this:

<s:property value="%{myMethod(#myVariable)}" />

My debug statement printed, but the value of myVariable was passed as null even though it has a value when it is printed via <s:property value="%{myVariable}" />

What is the correct syntax for passing a page variable to a Struts 2 method?

回答1:

<s:property value="%{myMethod(myVariable)}" />

is a correct syntax, but to get the value of the method that have a signature

public String myMethod(String value){
  return value;
}

required the getter for myVariable

public String getMyVariable() {
  return myVariable;
}

if you set the value to myVariable like

private String myVariable = "myValue";

then it should be printed in JSP. If the argument is other type it will be converted to String and the method will call.

回答2:

I think you are missing target object, ex

<s:property value="%{myTarget.myMethod(myVariable)}" />

More: How to pass parameter to method call in Struts 2 OGNL

来源：https://stackoverflow.com/questions/16288274/ognl-syntax-issue