the longest shadow you see in the day is 3\early in the morning and near the sunset...
The sun casts the longest shadows immediately after sunrise and immediately before sunset.
Just after sunrise, or just before sunset.
when its its sunrise and evening.
That depends where you are on the planet. Your shadow would be longest if you were standing on a rotational pole at the time of equinox. At this point your shadow would be infinity long as it would be "projected" into space. However as a rule of thumb one's shadow is longest when the sun is rising or setting but high enough to cast your shadow.
Morning
As can be observed on any sunny day, the shadows are longest at sunrise and at sunset.
A shadow is longest in the early morning or late afternoon when the angle of the sun is low in the sky. This occurs during sunrise and sunset when the sun is closest to the horizon, causing objects to cast longer shadows.
The time of day in which you will hardly have any shadow is during 12:00PM or noon. This is because the sun is directly above you, casting little to no shadow.
At dawn and dusk.
The time of day in which your shadow is longest is right before sunset, but early enough that there is still a good amount of sunlight. Your shadow is at it's shortest at 12 noon. As the sun goes further down, you are blocking more and more of its rays. The same could be said in the morning as the sun is rising. You will cast a long shadow that grows shorter until the sun is directly overhead.
Your shadow's position changes throughout the day due to the Earth's rotation. It is longest in the morning and evening when the sun is low in the sky, and shortest when the sun is directly overhead at noon. The angle of the sun in the sky affects the length and direction of your shadow.
noon