Question

当选项为String时，我在'select'中选择正确的值时遇到问题。我在论坛中找不到解决方案。

我在控制器中传递'kind'，我可以看到值很好但只在'select'中正确选择了Integer字段。具有String的那些总是显示第一个值，而不是'kind'中的一个传递。

我添加了我认为可能有用的代码有人可以帮忙吗？

我的HTML代码。表格中包含许多“选择”，但我留下了两个，第一个有效但第二个总是显示第一个选项：

 <form  role="form" th:action="@{/kind/update}"  th:object="${kind}" method="post">
    <div class="form-group col-md-4">
        <label for="replicates">No. of Replicates</label>
        <select id="replicates" class="form-control" style="width: 70%;" th:field="${kind.replicates}">
            <option th:each="rep: ${replicatesnumber}" th:value="${rep}" th:text="${rep}"> </option>
       </select>
   </div>
   <div class="form-group col-md-3">
       <label for="substrate">Substrate</label>
       <select id="substrate" class="form-control" th:field="${kind.substrate}">
           <option th:each="substrate: ${substrates}" th:value="${substrate}" th:text="${substrate}"> </option>
       </select>
   </div>
   <div class="box-footer">
    <button type="submit" class="btn btn-primary">Save</button>
    <a class="btn btn-primary" th:href="@{/division/edit/}+${kind.division.id}" role="button">Cancel</a>                                     
    </div>
</form>

控制器如下所示：

@Controller
@RequestMapping("/kind")
public class KindController {

    @Autowired 
    private KindService kindService;

    @ModelAttribute("replicatesnumber")
    public int[] getReplicates() {
        int[] reps = new int[3];
        reps[0] = 2;
        reps[1] = 4;
        reps[2] = 8;
        return reps;
    }

    @ModelAttribute("substrates")
    public List<String> getSubstrates() {
        return Arrays.asList("BP", "PP", "TP", "OGM", "Sand");
    } 

   @GetMapping(value= "/edit/{kindId}")
   public String viewDivision(@PathVariable Integer kindId, Model model){
       Kind kind= kindService.findById(kindId);
       model.addAttribute("kind",kind);
       return  "kind_edit";
   }

和实体：

@Entity
@Table(name = "kind", schema = "ostscourses")
public class Kind implements java.io.Serializable {

private Integer id;
private Division division;
private String name;
private Integer germinationDays;
private Integer firstCount;
private Integer replicates;
private Boolean dark;
private Integer chill;
private String temperature;
private String substrate;
private Integer noSeeds;
private List<Sample> samples;

public Kind() {
}

public Kind(Integer id, Division division) {
    this.id = id;
    this.division = division;
}

public Kind(Integer id, Division division, String name, Integer germinationDays, Integer firstCount, Integer replicates, Boolean dark, Integer chill, String temperature, String substrate, Integer noSeeds, List<Sample> samples) {
    this.id = id;
    this.division = division;
    this.name = name;
    this.germinationDays = germinationDays;
    this.firstCount = firstCount;
    this.replicates = replicates;
    this.dark = dark;
    this.chill = chill;
    this.temperature = temperature;
    this.substrate = substrate;
    this.noSeeds = noSeeds;
    this.samples = samples;
}

@Id
@Column(name = "id", unique = true, nullable = false)
public Integer getId() {
    return this.id;
}

public void setId(Integer id) {
    this.id = id;
}

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "division_id", nullable = false)
@JsonIgnore
public Division getDivision() {
    return this.division;
}

public void setDivision(Division division) {
    this.division = division;
}

@Column(name = "name", length = 25)
public String getName() {
    return this.name;
}

public void setName(String name) {
    this.name = name;
}

@Column(name = "germination_days")
public Integer getGerminationDays() {
    return this.germinationDays;
}

public void setGerminationDays(Integer germinationDays) {
    this.germinationDays = germinationDays;
}

@Column(name = "first_count")
public Integer getFirstCount() {
    return this.firstCount;
}

public void setFirstCount(Integer firstCount) {
    this.firstCount = firstCount;
}

@Column(name = "replicates")
public Integer getReplicates() {
    return this.replicates;
}

public void setReplicates(Integer replicates) {
    this.replicates = replicates;
}

@Column(name = "dark")
public Boolean getDark() {
    return this.dark;
}

public void setDark(Boolean dark) {
    this.dark = dark;
}

@Column(name = "chill")
public Integer getChill() {
    return this.chill;
}

public void setChill(Integer chill) {
    this.chill = chill;
}

@Column(name = "temperature", length = 10)
public String getTemperature() {
    return this.temperature;
}

public void setTemperature(String temperature) {
    this.temperature = temperature;
}

@Column(name = "substrate", length = 5)
public String getSubstrate() {
    return this.substrate;
}

public void setSubstrate(String substrate) {
    this.substrate = substrate;
}

@Column(name = "no_seeds")
public Integer getNoSeeds() {
    return this.noSeeds;
}

public void setNoSeeds(Integer noSeeds) {
    this.noSeeds = noSeeds;
}

@OneToMany(fetch = FetchType.LAZY, mappedBy = "kind")
@JsonIgnore
public List<Sample> getSamples() {
    return this.samples;
}

public void setSamples(List<Sample> samples) {
    this.samples = samples;
}

@Override
public int hashCode() {
    int hash = 3;
    hash = 47 * hash + Objects.hashCode(this.id);
    return hash;
}

@Override
public boolean equals(Object obj) {
    if (this == obj) {
        return true;
    }
    if (obj == null) {
        return false;
    }
    if (getClass() != obj.getClass()) {
        return false;
    }
    final Kind other = (Kind) obj;
    if (!Objects.equals(this.id, other.id)) {
        return false;
    }
    return true;
}

@Override
public String toString() {
    return "Kind{" + "id=" + id + ", name=" + name + ", germinationDays=" + germinationDays + ", firstCount=" + firstCount + ", replicates=" + replicates + ", dark=" + dark + ", chill=" + chill + ", temperature=" + temperature + ", substrate=" + substrate + ", noSeeds=" + noSeeds + '}';
}

}

Answer 1

好吧，我刚刚找到了一个解决方案，用select

中我需要的值创建枚举

public enum SubstrateType{
    BP,
    PP,
    TP,
    OGM,
    Sand;
}

在我的控制器中：

@ModelAttribute("substrates")
public SubstrateType[] getSubstrates() {
    return SubstrateType.values();
}

我知道它应该在没有枚举的情况下工作，因为我之前已经看过了。无论如何，我认为这是一个很好的练习。

选择从控制器传递的选项

1 个答案: