200+ Trắc nghiệm Lập trình nâng cao (có đáp án)

 " static void Main(string[] args) "

 " { "

 " int a = 30; "

 " ++a; "

 " Console.Write(a); "

 " Console.ReadLine(); "

 " "

“ }

 " "

" private void textBox2_KeyPress(object sender, KeyPressEventArgs e) "

 " { "

 " if (!char.IsDigit(e.KeyChar) && !char.IsControl(e.KeyChar)) "

 " { "

 " e.Handled = true; "

 " } "

 " } 

" "

" int tich, i; "

 " tich = 1; "

for(i=1;i

“dataGridView1.Rows[current].Selected = false;” & vbCrLf & _

“current = 0;” & vbCrLf & _

“dataGridView1.Rows[current].Selected = true;

 1. short x; "

 2. int y =100; "

 3. x = (short)y;

 " "

 " class Program "

" { "

 “ static void Main(string[] args) ”

 " { " & vbcrlf &

 " nguoi obj = new nhanvien(); "

 " } "

 “ } ”

" class nguoi "

 " { "

 " private string hoten; "

 " 1. public nguoi() { } "

 " 2. public nguoi(string name, int age) { } "

 " 3. public nguoi(string name) { } "

 " } 

“1. SqlConnection ketnoi = new SqlConnection(@"server=(local);"” & vbCrLf & _

“+"database=Quanlysinhvien; integrated security=true;");” & vbCrLf & _

“ 2. string truyvan = "delete from sinhvien";” & vbCrLf & _

“ 3. SqlCommand cmd = new SqlCommand(truyvan,ketnoi); & vbCrLf & _

“ 4. cmd.ExecuteReader();

“if (current >=dataGridView1.Rows.Count-2) “ _

“{“

“return;”

“}”

“dataGridView1.Rows[current].Selected = false;”

“current = current + 1;”

“dataGridView1.Rows[current].Selected = true;

“dataGridView1.Rows[current].Selected = false;”

“current = dataGridView1.Rows.Count-2;”

“dataGridView1.Rows[current].Selected = true;

 " int tich, i; "

" tich = 1; "

for (i = 1; i

" "

" class nhanvien : nguoi "

" { } "

" class nguoi "  

" { "

 " private string hoten; "

 " public string getName "

" {get { return hoten; }} "

 " public void hienthi(){ } "

 " } "

 "