====>java
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
public static void test1() throws ScriptException {
String str = "(a >= 0 && a <= 5)";
ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("js");
engine.put("a", 6);
Object result = engine.eval(str);
System.out.println("结果类型:" + result.getClass().getName() + ",计算结果:" + result);
}
public static void test2() throws ScriptException {
String str = "43*(2 + 1.4)+2*32/(3-2.1)";
ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("js");
Object result = engine.eval(str);
System.out.println("结果类型:" + result.getClass().getName() + ",计算结果:" + result);
}
public static void main(String[] args) {
try {
test1();
test2();
} catch (ScriptException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
jdk1.6中可以直接这样用
=========>js
<input type=
"text"
id=
"text1"
value=
"4"
/>
<input type=
"text"
id=
"text2"
value=
"9"
/>
<input type=
"text"
id=
"text3"
value=
"5"
/>
<input type=
"text"
id=
"text4"
value=
"6"
/>
<input type=
"text"
id=
"text5"
value=
"2"
/>
<input type=
"button"
value=
"计算"
onclick=
"func();"
/>
<script type=
"text/javascript"
>
function
func() {
var
str =
"(A+B+C)*D/E"
;
var
A = parseFloat(document.getElementById(
"text1"
).value);
var
B = parseFloat(document.getElementById(
"text2"
).value);
var
C = parseFloat(document.getElementById(
"text3"
).value);
var
D = parseFloat(document.getElementById(
"text4"
).value);
var
E = parseFloat(document.getElementById(
"text5"
).value);
var
num = eval(str);
alert(num);
}
</script>
例如：
