Read a CSV file in apex code / visualforce

Read_csv_file.txt

public  class Corpogas_ReadCSVController {
	
	public Blob csvFileBody{get;set;}
	public string csvAsString{get;set;}
	public String[] csvFileLines{get;set;}


	public List<OpeationDirectoryInformation> directory;

	public List<OpeationDirectoryInformation> getDirectory(){
		return this.directory;
	}

	public void setDiretory(List<OpeationDirectoryInformation> list_directory){
		this.directory = list_directory;
	}

	public Corpogas_ReadCSVController(){
		csvFileLines = new String[]{};
		
	}
	  
	public void importCSVFile(){
		
		Set<String> set_account_Information  = new Set<String>();
		Set<String> set_contact_Information  = new Set<String>();
		Map<String,String> map_account = new Map<String,String>();
		Map<String,String> map_contact = new Map<String,String>();

		directory    = new List<OpeationDirectoryInformation>();

		try{
	       
			csvAsString  = csvFileBody.toString();
			csvFileLines = csvAsString.split('\r'); 

	       	for(Integer i=1;i<csvFileLines.size();i++){

	       		string[] csvRecordData = csvFileLines[i].split(',');
	       		set_account_Information.add(csvRecordData[0]);
	       		set_contact_Information.add(csvRecordData[6]);
	       	}

	       	for(Account accs:[Select Id,No_Estacion__c from Account where No_Estacion__c IN:set_account_Information]){
	       		System.debug('### AccountNumber: '+accs.No_Estacion__c);
	       		map_account.put(String.valueOf(accs.No_Estacion__c),accs.Id);
	       	}

	       	for(Contact contact:[Select Id,Email from Contact where Email IN:set_contact_Information]){
	       		map_contact.put(contact.Email,contact.Id);
	       	}
           	for(Integer i=1;i<csvFileLines.size();i++){			

				string[] csvRecordData = csvFileLines[i].split(',');
				
				OpeationDirectoryInformation directory_record = new OpeationDirectoryInformation();
				
				if(map_account.get(csvRecordData[0])!= null){

					directory_record.accountNumber = map_account.get(csvRecordData[0]); //noestacion 
				}
				else{
					directory_record.accountNumber = csvRecordData[0];
				}
				
				directory_record.gpvFirstName  = csvRecordData[1];
				directory_record.gpvLastName   = csvRecordData[2];
				directory_record.gpvRadio      = csvRecordData[3];
				directory_record.gpvPhone      = csvRecordData[4];
				directory_record.gpvEmail      = csvRecordData[5].replace('..','.');
				
				if(map_contact.get(csvRecordData[6])!=null){
					directory_record.ggEmail       = map_contact.get(csvRecordData[6]);
				}
				else{
					directory_record.ggEmail       = csvRecordData[6];
				}
				

				directory.add(directory_record);
			}
        }
        catch (Exception e)
        {	
        	System.debug('### Error: '+e.getMessage());
        	ApexPages.Message errorMessage = new ApexPages.Message(ApexPages.severity.ERROR,'An error has occured while importin data Please make sure input csv file is correct');
            ApexPages.addMessage(errorMessage);
        }  
	}

	public PageReference updateDirectory(){
		List<Contact> contact_insert = new List<Contact>();
		for(OpeationDirectoryInformation operations:directory){
			Contact c     = new Contact();
			c.FirstName   = operations.gpvFirstName;
			c.LastName    = operations.gpvLastName;
			c.Email       = operations.gpvEmail;
			c.ReportsToId = operations.ggEmail;
			c.AccountId   = operations.accountNumber;
			contact_insert.add(c);
		}

		insert contact_insert;

		return null;
	}



	public class OpeationDirectoryInformation{
		public String accountNumber{get;set;}
		public String gpvFirstName{get;set;}
		public String gpvLastName{get;set;}
		public String gpvRadio{get;set;}
		public String gpvPhone{get;set;}
		public String gpvEmail{get;set;}
		public String ggEmail{get;set;}
	}
}


@isTest
private class TEST_Corpogas_ReadCSVController {
	
	@isTest static void test_method_one() {
		
		//preparing information in String
		String csv_template = '81,firstname1,lastname1,52*40867*131,91180170,pedro.morales@corpogas.com.mx,rufina.ruiz@corpogas.com.mx\r91,firstname1,lastname1,52*40867*131,91180170,pedro.morales@corpogas.com.mx,rufina.ruiz@corpogas.com.mx';
		Blob blob_csv = Blob.valueOf(csv_template);

		Corpogas_ReadCSVController csvController = new Corpogas_ReadCSVController();
		Corpogas_ReadCSVController.OpeationDirectoryInformation wrapper = new Corpogas_ReadCSVController.OpeationDirectoryInformation();
		csvController.csvFileBody = blob_csv;
		List<Corpogas_ReadCSVController.OpeationDirectoryInformation> lis_wrapper = csvController.getDirectory();
		csvController.setDiretory(lis_wrapper);

		csvController.importCSVFile();
	}

		@isTest static void test_method_error() {
		
		//preparing information in String
		String csv_template = '123][[][][][][';
		Blob blob_csv = Blob.valueOf(csv_template);

		Corpogas_ReadCSVController csvController = new Corpogas_ReadCSVController();
		Corpogas_ReadCSVController.OpeationDirectoryInformation wrapper = new Corpogas_ReadCSVController.OpeationDirectoryInformation();
		csvController.csvFileBody = blob_csv;
		List<Corpogas_ReadCSVController.OpeationDirectoryInformation> lis_wrapper = csvController.getDirectory();
		csvController.setDiretory(lis_wrapper);

		csvController.importCSVFile();
		PageReference re = csvController.updateDirectory();
	}
}

<apex:page controller="Corpogas_ReadCSVController">
    <apex:form >
        <apex:pagemessages />
        <apex:pageBlock >
            <apex:pageBlockSection columns="4"> 
                  <apex:inputFile value="{!csvFileBody}"  filename="{!csvAsString}"/>
                  <apex:commandButton value="Import Directory" action="{!importCSVFile}"/>
                  <apex:commandButton value="Update Directory" action="{!updateDirectory}"/>
            </apex:pageBlockSection>
        </apex:pageBlock>
        <apex:pageBlock >
			
			<apex:pageblocktable value="{!directory}" var="dir">
				<apex:column value="{!dir.accountNumber}" />
				<apex:column value="{!dir.gpvFirstName}" />
				<apex:column value="{!dir.gpvLastName}" />
				<apex:column value="{!dir.gpvRadio}" />
				<apex:column value="{!dir.gpvPhone}" />
				<apex:column value="{!dir.gpvEmail}" />
				<apex:column value="{!dir.ggEmail}" />
        	</apex:pageblocktable>
     </apex:pageBlock>
   </apex:form>
</apex:page>

Doesn't work properly. Multiline cells are not handled correctly. You cannot just use split.