Question

请查看以下代码

<c:forEach var="patientBean" items="${requestScope['PatientBean']}">
                <tr>
                  <td><img src="images/img1.jpg" width="30px" height="30px"/></td>
                  <td><c:out value="${patientBean.FirstName}"/><c:out value="${patientBean.MiddleName}"/><c:out value="${patientBean.LastName}"/></td>
                  <td><c:out value="${patientBean.dob}"/></td>
                  <td><c:out value="${patientBean.sex}"/></td>

                  <td><form name="form1" method="post" action="allergies.jsp">
                    <label>
                      <input type="submit" name="view" id="1" value="View">
                    </label>
                 <input name="idPatient" type="hidden" value=<c:out value="${patientBean.idPatient}"/>>
                      </c:forEach>

我有一个名为PatientBean的bean。在servlet中，很多PatientBean被填充并添加到ArrayList。上面的代码显示了我如何尝试访问JSP中的ArrayList并获取其中的bean数据。

下面是Servlet，它将请求转发给JSP

request.setAttribute("patientBean", patientBeanList);
        RequestDispatcher requestDispatcher = request.getRequestDispatcher("patients.jsp");
        requestDispatcher.forward(request, response);

然而它确实没有用。没有显示数据。我做错了什么？

以下是PatientBean

/**
 *
 * @author Yohan
 */
public class PatientBean implements Serializable {

    private int idPatient;
    private String firstName;
    private String middleName;
    private String lastName;
    private Date dob;
    private String sex;

    /**
     * @return the idPatient
     */
    public int getIdPatient() {
        return idPatient;
    }

    /**
     * @return the firstName
     */
    public String getFirstName() {
        return firstName;
    }

    /**
     * @return the middleName
     */
    public String getMiddleName() {
        return middleName;
    }

    /**
     * @return the lastName
     */
    public String getLastName() {
        return lastName;
    }

    /**
     * @return the dob
     */
    public Date getDob() {
        return dob;
    }

    /**
     * @return the sex
     */
    public String getSex() {
        return sex;
    }

    /**
     * @param idPatient the idPatient to set
     */
    public void setIdPatient(int idPatient) {
        this.idPatient = idPatient;
    }

    /**
     * @param firstName the firstName to set
     */
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    /**
     * @param middleName the middleName to set
     */
    public void setMiddleName(String middleName) {
        this.middleName = middleName;
    }

    /**
     * @param lastName the lastName to set
     */
    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    /**
     * @param dob the dob to set
     */
    public void setDob(Date dob) {
        this.dob = dob;
    }

    /**
     * @param sex the sex to set
     */
    public void setSex(String sex) {
        this.sex = sex;
    }


}

Answer 1

你有

<c:forEach var="patientBean" items="${requestScope['PatientBean']}">

但

request.setAttribute("patientBean", patientBeanList);

请注意，属性名称区分大小写。因此${requestScope['PatientBean']}将找不到名为patientBean的请求属性。

因为你以前有过

<td><c:out value="${patientBean.dob}"/></td>

patientBean实际上会引用patientBeanList，您可能想要重命名一些内容。

您的请求属性应调用patientBeans。

request.setAttribute("patientBeans", patientBeanList);

然后您可以访问它

<c:forEach var="patientBean" items="${patientBeans}">

您的var现在允许您使用${patientBean}来引用items中的各个元素。

无法使用JSTL访问bean

1 个答案: