private void btnDropTable_Click(object sender, EventArgs e)
{
if (lbxTable.SelectedIndex == -1)
{
MessageBox.Show("请选择表", "提示", MessageBoxButtons.OK, MessageBoxIcon.Warning);
}
else
{
TableF tableF = TableF.getTableF();
tableF.deleteTable(lbxTable.SelectedItem.ToString());
refreshAll();
}
}
public static DataTable readsql(string sql)
{
initialize(third);
initialize(operate);
//sql = "select a from student where sno='1234'";
string[] all = new string[10];
all[0] = "select";
all[1] = "insert";
all[2] = "delete";
all[3] = "update";
all[4] = "drop";
all[5] = "create";
string[] keyword = new string[10];
string[] first = new string[10];
string[] second = new string[10];
initialize(keyword);
initialize(first);
initialize(second);
int i;
for (i = 0; i < 10; i++)
{
keyword[i] = null;
}
while (i < sql.Length)
{
for (i = 0; sql[i] != ' ' && sql[i] != '\n'; i++)
{
keyword[0] = keyword[0] + sql[i];
k = 1;
}
if (k == 1 && sql[i] == ' ')
{
break;
}
}
int m = 0, n = 0;
k = 0;
if (keyword[0].ToLower() == all[0])//select
{
while (i < sql.Length)
{
first[m] = null;
for (; i < sql.Length && sql[i] != ' ' && sql[i] != '\n' && sql[i] != ','; i++)
{
first[m] = first[m] + sql[i];
k = 1;
}
if (first[m] != null && first[m].ToLower() == "from")
{
break;
}
if (k == 1)
{
m++;
}
i++;
}
keyword[1] = first[m];
for (; m < 10; m++)
{
first[m] = null;
}
k = 0;
while (i < sql.Length)
{
second[n] = null;
for (; i < sql.Length && sql[i] != '\n' && sql[i] != ',' && sql[i] != ' '; i++)
{
second[n] = second[n] + sql[i];
k = 1;
if (sql[i] == '>' || sql[i] == '<' || sql[i] == '=')
{
MessageBox.Show("未输入where，错误");
break;
}
}
if (second[n] != null && second[n].ToLower() == "where")
{
break;
}
if (k == 1)
{
n++;
k = 0;
}
i++;
}
keyword[2] = "where";
for (; n < 10; n++)
{
second[n] = null;
}
k = 0;
int s;
//去second[] null
for (s = 0; s < second.Length; s++)
{
if (second[s] == null)
{
break;
}
}
string[] second0 = new string[s];
for (int s1 = 0; s1 < s; s1++)
{
second0[s1] = second[s1];
}
//去first[] null
for (s = 0; s < first.Length; s++)
{
if (first[s] == null)
{
break;
}
}
string[] first0 = new string[s];
for (int s1 = 0; s1 < s; s1++)
{
first0[s1] = first[s1];
}
int[] index = new int[s];
for (int s1 = 0; s1 < s; s1++)
{
index[s1] = getindex(second0, first0[s1]);
first0[s1] = getname(first0[s1]);
}
if (first0[0] == "*")
{
first0 = null;
}
DataF dataF = DataF.getDataF();
if (i == sql.Length)
{
DataTable dt0 = dataF.selectData(second0, first0, index, null);
return(dt0);
}
else
{
DataTable dt = dataF.selectData(second0, first0, index, getcondition(second0, i, sql));//select查询
return(dt);
}
}
else if (keyword[0].ToLower() == all[1])//insert
{
int ins = 0;
k = 0;
while (i < sql.Length)
{
second[ins] = null;
for (; i < sql.Length && sql[i] != '(' && sql[i] != ')' && sql[i] != ',' && sql[i] != ' ' && sql[i] != '\n'; i++)
{
second[ins] = second[ins] + sql[i];
k = 1;
}
if (k == 1)
{
ins++;
k = 0;
}
//second[1]是表名
if (sql[i] == '(')
{
break;
}
i++;
}
//写到这！！！！！
int ins1 = 0;
k = 0;
while (i < sql.Length - 1)
{
third[ins1] = null;
for (; sql[i] != '\'' && sql[i] != '(' && sql[i] != ')' && sql[i] != ',' && sql[i] != ' ' && sql[i] != '\n' && i < sql.Length - 1; i++)
{
third[ins1] = third[ins1] + sql[i];
k = 1;
}
if (k == 1)
{
ins1++;
k = 0;
}
if (sql[i] == ')')
{
break;
}
i++;
}
//third[]中存储values
int s;
for (s = 0; s < third.Length; s++)
{
if (third[s] == null)
{
break;
}
}
string[] third1 = new string[s];
for (int s1 = 0; s1 < s; s1++)
{
third1[s1] = third[s1];
}
//DataF dataF = new DataF();
DataF dataF = DataF.getDataF();
List <object> list = new List <object>();
for (int s1 = 0; s1 < s; s1++)
{
list.Add(isname(third1[s1]));
}
//object[] b = (object[])ArrayList.Adapter((Array)third).ToArray(typeof(object));
dataF.insert(second[1], list);
DataTable dt = null;
return(dt);
}
else if (keyword[0].ToLower() == all[2])//delete
{
int ins = 0;
k = 0;
while (i < sql.Length)
{
second[ins] = null;
for (; i < sql.Length && sql[i] != '(' && sql[i] != ')' && sql[i] != ',' && sql[i] != ' ' && sql[i] != '\n'; i++)
{
second[ins] = second[ins] + sql[i];
k = 1;
}
//second[1]是表名
if (second[ins] != null && second[ins].ToLower() == "where")
{
break;
}
if (k == 1)
{
ins++;
k = 0;
}
i++;
}
//获取condition
//DataF dataf = new DataF();
DataF dataf = DataF.getDataF();
string[] second1 = new string[1];
second1[0] = second[1];
dataf.delete(second[1], getcondition(second1, i, sql));
DataTable dt = null;
return(dt);
}
else if (keyword[0].ToLower() == all[3])//update
{
int ins = 0;
k = 0;
while (i < sql.Length)
{
second[ins] = null;
for (; i < sql.Length && sql[i] != '(' && sql[i] != ')' && sql[i] != ',' && sql[i] != ' ' && sql[i] != '\n'; i++)
{
second[ins] = second[ins] + sql[i];
k = 1;
}
//second[0]是表名
if (second[ins] != null && second[ins].ToLower() == "set")
{
break;
}
if (k == 1)
{
ins++;
k = 0;
}
i++;
}
int upd = 0, upd1 = 0, k1 = 0;
string[] first1 = new string[10];
k = 0;
while (i < sql.Length)
{
k1 = 0;
first[upd] = null;
first1[upd1] = null;
for (; i < sql.Length && sql[i] != ',' && sql[i] != ' ' && sql[i] != '\n'; i++)
{
if (sql[i] == '=')
{
k1 = 1;
}
if (k1 == 0)
{
first[upd] = first[upd] + sql[i];
}
else
{
if (sql[i] != '=' && sql[i] != '\'')
{
first1[upd1] = first1[upd1] + sql[i];
}
}
k = 1;
}
if (first[upd] != null && first[upd].ToLower() == "where")
{
first[upd] = null;
first1[upd1] = null;
break;
}
if (k == 1)
{
upd++;
upd1++;
k = 0;
}
i++;
}
//获取condition
//去null
string[] second1 = new string[1];
second1[0] = second[1];
int s;
for (s = 0; s < first.Length; s++)
{
if (first[s] == null)
{
break;
}
}
string[] first0 = new string[s];
for (int s1 = 0; s1 < s; s1++)
{
first0[s1] = first[s1];
}
for (s = 0; s < first1.Length; s++)
{
if (first1[s] == null)
{
break;
}
}
object[] first10 = new string[s];
for (int s1 = 0; s1 < s; s1++)
{
first10[s1] = isname(first1[s1]);
}
//DataF dataf = new DataF();
DataF dataf = DataF.getDataF();
dataf.update(second[0], first0, first10, getcondition(second1, i, sql));
DataTable dt = null;
return(dt);
}
else if (keyword[0] == all[4])//drop
{
int ins = 0;
k = 0;
while (i < sql.Length)
{
second[ins] = null;
for (; i < sql.Length && sql[i] != '(' && sql[i] != ')' && sql[i] != ',' && sql[i] != ' ' && sql[i] != '\n'; i++)
{
second[ins] = second[ins] + sql[i];
k = 1;
}
//second[1]是表名
/*if (second[ins].ToLower() == "set")
* break;*/
if (k == 1)
{
ins++;
k = 0;
}
i++;
}
//11111111
TableF tablef = TableF.getTableF();
tablef.deleteTable(second[1]);
}
else if (keyword[0].ToLower() == all[5])//create
{
int ins = 0;
k = 0;
while (i < sql.Length)
{
second[ins] = null;
for (; i < sql.Length && sql[i] != '(' && sql[i] != ')' && sql[i] != ',' && sql[i] != ' ' && sql[i] != '\n'; i++)
{
second[ins] = second[ins] + sql[i];
k = 1;
}
//second[1]是表名
if (sql[i] == '(')
{
break;
}
if (k == 1)
{
ins++;
k = 0;
}
i++;
}
//1111111111
TableF tableF = TableF.getTableF();
Table table = new Table(second[1]);
int c = 0;
k = 0;
bool nul = false, key = false;
while (i < sql.Length)
{
third[c] = null;
for (; i < sql.Length && sql[i] != ' ' && sql[i] != '\n' && sql[i] != '(' && sql[i] != ')' && sql[i] != '[' && sql[i] != ']'; i++)
{
if (sql[i] == ',')
{
break;
}
third[c] = third[c] + sql[i];
k = 1;
}
if (c == 2)
{
bool num = true;
for (int i1 = 0; third[2] != null && i1 < third[c].Length; i1++)
{
if (third[2] != null && !Char.IsNumber(third[2], i1))
{
num = false;
break;
}
}
if (third[2] == null || num != true)
{
c++;
third[c] = third[c - 1];
third[c - 1] = "0";
}
}
if (c == 3)
{
if (third[c] != null && third[c].ToLower() == "null")
{
nul = true;
}
else if (third[c] != null && third[c].ToLower() == "iskey")
{
key = true;
}
else if (third[c] != null)
{
MessageBox.Show("是否为空或是否为主键输入错误！");
}
}
if (c == 4)
{
if (third[c] != null && third[c].ToLower() == "iskey")
{
key = true;
}
else if (third[c] != null)
{
MessageBox.Show("是否为主键输入错误！");
}
}
if (sql[i] == ',' || sql[i] == ')')
{
if (third[2] == null)
{
third[2] = "0";
}
//获取枚举值en
Type ob = typeof(Field.Type);
//Field.Type ob = new Field.Type();
//ob = Field.Type.Int;
Array ar = Enum.GetValues(ob);
int en;
for (en = 0; en < ar.Length; en++)
{
if (third[1].ToLower() == ar.GetValue(en).ToString().ToLower())
{
break;
}
}
Field field = new Field(third[0], (Field.Type)en, Convert.ToInt16(third[2]), nul, key);
table.addField(field);
}
if (sql[i] == ')')
{
break;
}
if (sql[i] == ',')
{
for (int i1 = 0; i1 < third.Length; i1++)
{
third[i1] = null;
}
c = 0;
k = 0;
}
if (k == 1)
{
c++;
k = 0;
}
i++;
}
tableF.addTable(table);
DataTable dt = null;
return(dt);
}
else
{
MessageBox.Show("语句输入错误！");
DataTable dt = null;
return(dt);
}
DataTable dt1 = null;
return(dt1);
}