/// <summary>
/// 返回 字符串 内容
/// </summary>
/// <returns>返回 字符串 内容</returns>
public override string ToString()
{
__sql.Append("(");
__sql.Append(__args[0]);
__sql.Append(")");
return(__sql.ToString());
}
private UpdateBuilder <T> InternalAppend(string field, Expression value)
{
if (!__sql.IsEmpty)
{
__sql.Append(", ");
}
__sql.AppendFormat("{0} = ", field);
base.Visit(value);
return(this);
}
private GetBuilder <T> Select(string columnName)
{
if (__select.IsNull() || __select[0] == '*')
{
__select = new STR();
}
if (!__select.IsEmpty)
{
__select.Append(", ");
}
__select.Append(columnName);
return(this);
}
/// <summary>
/// 处理二元运算表达式
/// </summary>
/// <param name="expression">表达式</param>
/// <returns>表达式</returns>
protected override Expression VisitBinary(BinaryExpression expression)
{
__sql.Append("(");
this.Visit(expression.Left);
__sql.Append(this.GetOperator(expression.NodeType));
this.Visit(expression.Right);
__sql.Append(")");
return(expression);
}
private GetBuilder <T> OrderBy(bool desc, string orderby)
{
if (__orderby.IsNull())
{
__orderby = new STR();
}
if (string.IsNullOrEmpty(orderby))
{
return(this);
}
if (!__orderby.IsEmpty)
{
__orderby.Append(", ");
}
__orderby.Append(orderby);
if (desc)
{
__orderby.Append(" DESC ");
}
return(this);
}
private string ParseString()
{
ConsumeToken(); // "
s.Length = 0;
int runIndex = -1;
while (index < json.Length)
{
var c = json[index++];
if (c == '"')
{
if (runIndex != -1)
{
if (s.Length == 0)
{
return(new string(json, runIndex, index - runIndex - 1));
}
s.Append(json, runIndex, index - runIndex - 1);
}
return(s.ToString());
}
if (c != '\\')
{
if (runIndex == -1)
{
runIndex = index - 1;
}
continue;
}
if (index == json.Length)
{
break;
}
if (runIndex != -1)
{
s.Append(json, runIndex, index - runIndex - 1);
runIndex = -1;
}
switch (json[index++])
{
case '"':
s.Append('"');
break;
case '\\':
s.Append('\\');
break;
case '/':
s.Append('/');
break;
case 'b':
s.Append('\b');
break;
case 'f':
s.Append('\f');
break;
case 'n':
s.Append('\n');
break;
case 'r':
s.Append('\r');
break;
case 't':
s.Append('\t');
break;
case 'u':
var remainingLength = json.Length - index;
if (remainingLength < 4)
{
break;
}
// parse the 32 bit hex into an integer codepoint
var codePoint = ParseUnicode(json[index], json[index + 1], json[index + 2], json[index + 3]);
s.Append((char)codePoint);
// skip 4 chars
index += 4;
break;
}
}
throw new Exception(Localization.Resources.UnexpectedlyReachedEndOfStringException);
}
protected override Expression VisitBinary(BinaryExpression expression)
{
this.Visit(expression.Left);
__select.Append(this.GetOperator(expression.NodeType));
var temp = __needdelimiter;
__needdelimiter = false;
this.Visit(expression.Right);
__needdelimiter = temp;
return(expression);
}
/// <summary>
/// 处理构造函数调用表达式
/// </summary>
/// <param name="expression">表达式</param>
/// <returns></returns>
protected override Expression VisitNew(NewExpression expression)
{
var members = expression.Members;
var arguments = expression.Arguments;
var len = members.Count < arguments.Count ? members.Count : arguments.Count;
for (int i = 0; i < len; i++)
{
this.Visit(arguments[i]);
if (__isrowno)
{
__rownoname = members[i].Name;
__isrowno = false;
continue;
}
if (arguments[i].NodeType == ExpressionType.MemberAccess && (arguments[i] as MemberExpression).Member.Name == members[i].Name)
{
continue;
}
select.Append(context.Database._dbType.EscapeNewName(members[i].Name));
}
return(expression);
}
private WhereBuilder Append(Expression expression, string type)
{
if (expression != null)
{
if (!__sql.IsEmpty)
{
__sql.Append(type);
}
base.Visit(expression);
}
return(this);
}
