CODEWITHSUNDEEP
c#string
user1865670
user1865670

Reputation:

Getting certain string blocks from a STRING

Here is a text: string txt holds this value.

CREATE TABLE table_name1 ( column_name11231 data_type, column_name232 data_type, column_name3 data_type, .... )

CREATE TABLE table_name2 ( column_name1 data_type, column_name2 data_type, column_name3 data_type, .... )

CREATE TABLE table_name3 ( column_name1231 data_type, column_name2 data_type, column_name3 data_type, .... )

CREATE TABLE table_name4 ( column_name1231 data_type, column_name1232 data_type, column_name1233 data_type, .... )

this is a sample. i will read it from a text file. then i just want to take each CREATE TABLE command in a string array. how could i take it? I have tried split and substring. but that was foolish. I have done it with a silly and uneffective way.

here is it:

string[] totalSp = Regex.Split(txt, "CREATE TABLE");
string[] output = new string[totalSp.Length-1];

for (int i = 1; i < totalSp.Length; i++ )
{
output[i - 1] = "CREATE TABLE " + totalSp[i].Replace("\r\n", "");
}

this give me the desired output. but i now this is poor coding. cannot I do it any simplier way?

Upvotes: 1

Views: 73

Answers (2)

Tim S.
Tim S.

Reputation: 56536

You can use this regex to find the statements, as long as you're not going to have much variation in the input.

var matches = Regex.Matches(txt, @"^CREATE TABLE .+", RegexOptions.Multiline);
string[] myArray = matches.Cast<Match>().Select(x => x.ToString()).ToArray();

Upvotes: 1

Servy
Servy

Reputation: 203817

You can use File.ReadLines to get the lines, and it's easy enough to filter the empty lines out without regexes.

var commands = File.ReadLines("filename.txt")
    .Where(line => !string.IsNullOrEmpty(line))
    .ToArray();

If there are other commands in the file besides create table then you can add a simple filter for that too. Just add the below command after the other filter:

.Where(line => line.StartsWith("CREATE TABLE"))

Upvotes: 0

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