I know I am forgetting to remember how to do this and it is late.
I want to, in an elegant manner, build a placeholder list for a munged sql command.
Have a command with an arbitrary number of parameters, need to build ?,?,?
Did I mention that it was a wet brain fart? this is what came out:
You are welcome to make me feel like more of an idiot if you just remember me what I am forgetting. ;-)
Ok, looks like I should be calling it a night.
Both you guys confirmed what I was doing before going off the deep end.
This is my name list,
string names = string.Join(",", _command.Parameters.Cast<SQLiteParameter>().Select(p => p.Pa开发者_运维百科rameterName).ToArray());
And I just replaced the p.Name with '?'
string vals = string.Join(",", _command.Parameters.Cast<object>().Select(p => "?").ToArray());
But for some reason I did not approve.
Thanks.
Well, this suggests itself:
string x = string.Join(",", Enumerable.Repeat("?", count).ToArray());
In .NET 4 this can be simplified slightly as string.Join
has new overloads:
string x = string.Join(",", Enumerable.Repeat("?", count));
On the other hand, I'd be tempted to just do it with a loop:
StringBuilder builder = new StringBuilder();
for (int i = 0; i < count; i++)
{
builder.Append("?,");
}
builder.Length--; // Remove trailing ,
return builder.ToString();
Either way I'd put it in a separate method, so the brevity isn't likely to matter.
Along the lines of @Jon's answer:
string.Join(",", _command.Parameters.Cast<object>().Select(p => "?").ToArray())
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