Sometimes we need to read a CSV file in a Visualforce Page. Here is an example to read a CSV file and display it in Visualforce Page. Below example reads a CSV file having Account records in it and displays them in a table.

CSV file format used in this example:

Controller:

Public class Sample {
    
    public Blob csvFileBody {get;set;}
    Public string csvAsString {get;set;}
    Public String[] csvFileLines {get;set;}
    Public String[] inputValues {get;set;}
    Public List<string> fieldList {get;set;}
    Public List<account> sObjectList {get;set;}
    
    public Sample(){
        csvFileLines = new String[]{};
            fieldList = New List<string>();
        sObjectList = New List<sObject>(); 
    }
    
    Public void readcsvFile(){
        String hexResult = EncodingUtil.convertToHex(csvFileBody);
        final Integer bytesCount = hexResult.length() >> 1;
        String[] bytes = new String[bytesCount];
        for(Integer i = 0; i < bytesCount; ++i){
            bytes[i] =  hexResult.mid(i << 1, 2);
        }
        csvAsString = EncodingUtil.urlDecode('%' + String.join(bytes, '%'), 'ISO-8859-1');
        csvFileLines = csvAsString.split('\n');
        inputValues = new String[]{};
            
            for(string st:csvfilelines[0].split(',')){
                fieldList.add(st); 
            }
        
        for(Integer i=1; i<csvfilelines.size(); i++){
            Account accRec = new Account() ;
            string[] csvRecordData = csvFileLines[i].split(',');
            accRec.Name = csvRecordData[0] ;             
            accRec.AccountNumber = csvRecordData[1];
            accRec.Type = csvRecordData[2];
            accRec.Industry = csvRecordData[3];                                                                               
            sObjectList.add(accRec);   
        }
    }
}

Visualforce Page:

<apex:page controller="Sample">
    <apex:form>
        <apex:pageBlock>
            <apex:panelGrid columns="2"> 
                <apex:inputFile value="{!csvFileBody}"  filename="{!csvAsString}"/>
                <apex:commandButton value="Read CSV" action="{!readcsvFile}"/>
            </apex:panelGrid>
        </apex:pageBlock>
        <apex:pageBlock>
            <apex:pageblocktable value="{!sObjectList}" var="rec">
                <apex:column value="{!rec.Name}" />
                <apex:column value="{!rec.AccountNumber}"/>
                <apex:column value="{!rec.Type}" />
                <apex:column value="{!rec.Industry}" />
            </apex:pageblocktable>
        </apex:pageBlock>
    </apex:form>
</apex:page>

Output: