通过 wcf 将数据存储到数据库时出现错误。我正在通过文本框从 android 客户端获取输入。 错误：参数化查询“(@ID nvarchar(4000),@Name nvarchar(4000),@Project nvarchar(4000)”需要参数“@ID”，但未提供该参数。
数据插入的c#代码是
[DataContract]
public class studentinfo
{
[DataMember(Name = "ID")]
public string ID { get; set; }
[DataMember(Name = "Name")]
public string Name { get; set; }
[DataMember(Name = "Project")]
public string Project { get; set; }
[DataMember(Name = "Result")]
public string Result { get; set; }
}
[OperationContract]
[WebInvoke(Method = "POST", RequestFormat = WebMessageFormat.Json, ResponseFormat = WebMessageFormat.Json, UriTemplate = "SaveData")]
void SaveData(studentinfo studentinfo);
public void SaveData(studentinfo studentinfo)
{
SqlConnection con;
con = new SqlConnection(ConfigurationManager.ConnectionStrings["Myproject.Properties.Settings.MyConnection"].ConnectionString);
if (con.State == ConnectionState.Closed)
{
con.Open();
}
SqlCommand cmd = new SqlCommand("INSERT INTO Result (ID,Name,Project,Result) values(@ID,@Name,@Project,@Result)", con);
cmd.Parameters.AddWithValue("@ID", studentinfo.ID);
cmd.Parameters.AddWithValue("@Name", studentinfo.Name);
cmd.Parameters.AddWithValue("@Project", studentinfo.Project);
cmd.Parameters.AddWithValue("@Result", studentinfo.Result);
int Valid = cmd.ExecuteNonQuery();
con.Close();
}
编辑：这是android客户端代码：
public class MarksActivity extends Activity {
private final static String SERVICE_URI = "http://10.0.2.2:51220/Service1.svc";
Button btnsave, btncal;
EditText txtid, txtname, txtproject, txtviva, txtpres, txtconfi, txtsystem, txttotal;
double h=0;
double s=0;
double x=0;
double y=0;
double z=0;
String text;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.marks);
btnsave=(Button)findViewById(R.id.btnsave);
text = "";
btncal=(Button)findViewById(R.id.btncal);
txtid=(EditText)findViewById(R.id.txtid);
txtname=(EditText)findViewById(R.id.txtname);
txtproject=(EditText)findViewById(R.id.txtproject);
txttotal=(EditText)findViewById(R.id.txttotal);
txtviva=(EditText)findViewById(R.id.txtviva);
txtpres=(EditText)findViewById(R.id.txtpres);
txtconfi=(EditText)findViewById(R.id.txtconfi);
txtsystem=(EditText)findViewById(R.id.txtsystem);
btnsave.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
saveData();
}
});
}
public void saveData() {
try{
boolean isValid = true;
h=Double.parseDouble(txtviva.getText().toString());
s=Double.parseDouble(txtpres.getText().toString());
x=Double.parseDouble(txtconfi.getText().toString());
y=Double.parseDouble(txtsystem.getText().toString());
z= h+s+x+y;
txttotal.setText(Double.toString(z));
if (isValid) {
// POST request to <service>/SaveVehicle
//Connect to the server
HttpPost httpPost=new HttpPost(SERVICE_URI +"/SaveData");
httpPost.setHeader("Accept", "application/json");
httpPost.setHeader("Content-type", "application/json");
// Build JSON string
JSONStringer getdata = new JSONStringer()
.object()
.key("studentinfo")
.object()
.key("ID").value(txtid.getText().toString())
.key("Name").value(txtname.getText().toString())
.key("Project").value(txtproject.getText().toString())
.key("Result").value(txttotal.getText().toString())
.endObject()
.endObject();
StringEntity entity = new StringEntity(getdata.toString());
httpPost.setEntity(entity);
// Send request to WCF service
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpResponse response = httpClient.execute(httpPost);
Log.d("WebInvoke", "Saving : " + response.getStatusLine().getStatusCode());
// Reload plate numbers
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
我确实尝试了其他答案中提供的一些方法，但无法解决这个问题。请帮我解决它