在下面的 listview 中显示名字和号码，这些数据都是从数据库中获取。当我删除比如数字区域是 "123456"时，能正常运行。但是问题是不能删除一些 list items ，比如它的数字区域是 "888-888-00"。
我使用的代码 ：
DatabaseHelpher.java
private static final String KEY_NAME = "name";
private static final String KEY_NUMBER = "number";
public void deleteContacts(String name, String number){
//Raw Query wont work for Deletion
db = this.getWritableDatabase();
System.out.println("deleted number: "+number+"name: "+name);
String deleteQuery = "Delete from "+CONTACTS_TABLE_NAME+" where "+KEY_NUMBER+" = "+number;
//db.rawQuery("Delete from "+CONTACTS_TABLE_NAME+" where "+KEY_NUMBER+" = "+number, null);
db.execSQL(deleteQuery);
db.close();
}
MainActivity.java
在 oncreate() method 方法中包括：
selectedListView.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
final HashMap<String, String> toDelete = (HashMap<String, String>) selectedListView.getItemAtPosition(position);
AlertDialog.Builder deleteDialog = new AlertDialog.Builder(MainActivity.this);
deleteDialog.setTitle("Confirm Delete...");
deleteDialog.setMessage("Are you sure you want delete this '"+toDelete.get("name")+"' Contact?");
deleteDialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dataBaseHelpher.deleteContacts(toDelete.get("name"), toDelete.get("number"));
dialog.dismiss();
updateList();
}
});
deleteDialog.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
});
deleteDialog.show();
}
});
该回答引用ChatGPT
问题可能出现在 SQL 查询语句中。在 deleteContacts() 方法中，您正在使用以下语句：
String deleteQuery = "Delete from "+CONTACTS_TABLE_NAME+" where "+KEY_NUMBER+" = "+number;
如果 number 值包含字符（如 “-”），则此语句将会出错。为了解决这个问题，您需要将 number 值用引号括起来，以使 SQL 引擎将其识别为字符串。修改上述代码如下：
String deleteQuery = "Delete from "+CONTACTS_TABLE_NAME+" where "+KEY_NUMBER+" = '"+number+"'";
这将确保您的 deleteQuery 语句可以正确地删除包含字符的电话号码。
请注意，这里只是一个可能的解决方案。如果这个修改没有解决您的问题，那么问题可能出现在其他地方。